Hi all,
I'm looking for a solution that will allow me to send MP3 and video (either ripped ISO files or downloaded TV shows) to my home theater as well as a separate stereo in the living room.

Right now I rip my CDs on a PC in the office, move the files onto my ReadNAS duo in the basement. I can play music find across any PC on the network but have no way to play what I want through my good systems in the other rooms, since I don't have a computer hooked up to either system. Likewise, with video, if I download a TV show it goes to my local hard drive, then I burn it to CD and play it on the DVD player in the home theater--then just toss it out. Seems like a waste and a PITA to implement. I can't afford a new PC to dedicate to the home theatre at this point, nor would it be easy to implement, I don't think.

There's gotta be a modestly-priced and easily-implementable solution to do what I'm looking to do, but so far nobody I've asked has been able to point me in the right direction. Any thoughts?

Easy and inexpensive:
http://www.avsforum.com/avs-vb/showthread.php?t=635294

Please excuse my ignorance on the topic, but isn't that a game system? One of the links I saw also said it was supported on Linux, Mac, PC, etc...thus making it sound like a computer application.

What am I missing here? Really, all I want is a dedicated piece of hardware that plugs into my network, uses a remote, pulls content stored on a NAS box and plays it through my HT speakers/screen. I do not want another computer system in my home theater system (how do you input commands to a PC from 15 feet across the room? I'm not going to keyboard commands when I want to watch a movie, let alone figure out how to use a mouse on a couch).

My video content is either in ISO format (when I've ripped my own DVDs) or DivX/XviD AVI. Will this device/application play these formats?

XBMC runs on the original xbox (as well as newer devices now) after it has been softmodded and loaded with the xbmc software. It is still one of the best(if not the best) ways of accessing your media as well as internet media. It is extremely responsive and has great WAF (wife acceptance factor)! It is fairly easy to do nowadays with a little research. I love mine. The popcorn hour is also decent and around 200 or so depending on the model. And yes both of these will play your media.

Please excuse my ignorance on the topic, but isn't that a game system? One of the links I saw also said it was supported on Linux, Mac, PC, etc...thus making it sound like a computer application.

What am I missing here? Really, all I want is a dedicated piece of hardware that plugs into my network, uses a remote, pulls content stored on a NAS box and plays it through my HT speakers/screen. I do not want another computer system in my home theater system (how do you input commands to a PC from 15 feet across the room? I'm not going to keyboard commands when I want to watch a movie, let alone figure out how to use a mouse on a couch).

My video content is either in ISO format (when I've ripped my own DVDs) or DivX/XviD AVI. Will this device/application play these formats?

The xbox running XBMC will do everything you want, with a great interface. And you can buy them for less than $50 each.
I have 3 of them and can stream different things to each one all at the same time off my NAS.
I use a Harmony One Remote with the xbox in the main room and it integrates seamlessly with my HT. Ease of use is so simple anyone can pick up the harmony and listen to music, watch a movie, or scroll through my pictures.
I use different Harmony Remotes for the 2 boxes with the bedroom and computer room tv's.
(You dont use any keyboard or mouse with XBMC.)

Again, look at the link I provided. All the info is there.

BTW, all my movies are either iso format or avi. XBMC plays them flawlessly.

Is the an off-the-shelf solution? If so, where is it available for retail purchase?

Please understand that when it comes to my home theatre I'm strictly plug-and-play and wish to keep it that way; I have an Onkyo 605, an OPPO 971 and my FiOS DVR box and that's it (all controlled with an older Harmony 659 that I'm quite enamored with). I'm just not into DIY any more, I'm afraid, and any attempt to go in that direction at this juncture is a non-starter. I've also never played a computer game in my entire life (yes, there really IS such a person!) and haven't the foggiest on how these machines integrate to what I have. Wouldn't a game system be a waste of money for a non-game-player?

Is what I want not offered by the big names like Pioneer, Onkyo, Sony, etc?

Is the an off-the-shelf solution? If so, where is it available for retail purchase?

Please understand that when it comes to my home theatre I'm strictly plug-and-play and wish to keep it that way; I have an Onkyo 605, an OPPO 971 and my FiOS DVR box and that's it (all controlled with an older Harmony 659 that I'm quite enamored with). I'm just not into DIY any more, I'm afraid, and any attempt to go in that direction at this juncture is a non-starter. I've also never played a computer game in my entire life (yes, there really IS such a person!) and haven't the foggiest on how these machines integrate to what I have. Wouldn't a game system be a waste of money for a non-game-player?

Is what I want not offered by the big names like Pioneer, Onkyo, Sony, etc?

I have never played a video game on my xbox. I dont even own a single game for it.
I bought it just to use as a media streamer.
You do have to load XBMC on the xbox, though not difficult, may be more than you want to do from the sound of your post. Once its loaded, than the xbox is pretty much plug and play. As for how they integrate, they are just like any other comonent you already own. A component cable out to a tv, and analog or optical out for sound. (and of course a network plug to network to your NAS)

If you are looking for a plug and play, off the shelf solution, I would look into the popcorn hour as the poster above suggested. It will do what you want, though certainly not as inexpensive or elegant as the xbox. I believe they run about $200 dollars a unit.

At this time, Sony, Pioneer and Onkyo have nothing to offer as far as media streamers.

For TV shows that are recorded and played on your DVD player I used a recordable CD or DVD. That way I would just erase it when I was done rather than using a DVD-ROM or CD-ROM. Even then, that gets old pretty fast as well.

There are devices out there that support various formats. D-Link's MediaLounge series, Netgear and Popcorn Hour are some of the network media players that can be integrated into a home theater while leaving the PC in the other room. They use a network connection that is either wired using an ethernet cable to the computer or a wireless connection. Wired network connection is optimal for high bandwidth video and auido and low bandwidth video will work on wireless.

I have the D-Link DSM-520 but I'm pretty certian it will not handle the ISO format that you require. However, it will play mp3's, AVI's and Xvids. You may get mixed results on the video formats depending on how it was encoded.

I have had excellent results with .tp (renamed to .ts) files created by my Fusion tuner card. AVI's and Xvids have been mixed...sometimes they work really well or the audio is out of sync half way through the show.

For TV shows that are recorded and played on your DVD player I used a recordable CD or DVD. That way I would just erase it when I was done rather than using a DVD-ROM or CD-ROM. Even then, that gets old pretty fast as well.

There are devices out there that support various formats. D-Link's MediaLounge series, Netgear and Popcorn Hour are some of the network media players that can be integrated into a home theater while leaving the PC in the other room. They use a network connection that is either wired using an ethernet cable to the computer or a wireless connection. Wired network connection is optimal for high bandwidth video and auido and low bandwidth video will work on wireless.

I have the D-Link DSM-520 but I'm pretty certian it will not handle the ISO format that you require. However, it will play mp3's, AVI's and Xvids. You may get mixed results on the video formats depending on how it was encoded.

I have had excellent results with .tp (renamed to .ts) files created by my Fusion tuner card. AVI's and Xvids have been mixed...sometimes they work really well or the audio is out of sync half way through the show.

I also had a DSM-520 before finding XBMC.
Though it was plug and play easy, I fell in love with the xbox XBMC's elegant and easy interface, and that it will play anything (except Hd) that I throw at it.
I have hundreds of movies in iso, hundreds of avis, and some video.ts. The xbox plays them all perfectly.
From what I have heard, the Popcorn Hour plays most formats as well.

I'd never heard of a popcorn hour before and I will check it out. The XBMC does sound intriguing and if I could get one pre-configured I'd be game to at least give it a try. I just honestly don't want to deal with yet another PC on my LAN -- maintaining my work boxen is enough of a tax on my rapidly-greying brainpan. When I just want to watch some telly or listen to some tunes I honestly don't want to deal with yet more PC nonsense...I just want to sit in front of the screen and "potatoe" with minimal technical nonsense involved :)

I also read somewhere that the XBMC doesn't handle HD content, is this still correct? At present, my OPPO 971 upconverts SD to 720p and does an excellent job of it. Is there a way to replicate this upconversion with any of the solutions proposed? If I rip a physical disk to an ISO file and store it on my NAS, will I be able to see it in similar quality if played back through a PCH or XBMC device?

The xbox xbmc doesnt play HD content, but it DOES upconvert to either 720p or 1080i.
I would bet not quite as good as the oppo though, which I heard does excellent upconversion.

I really think the Popcorn Hour is what you should be looking at.
Seems it will do what you want as far as Music and movies. There is A LOT of info on here about it. I would look at that thread for specific info.

BTW, I dont own a Popcorn Hour, but have heard many good things about it.