I know this may sound stupid, but do you have the antenna aimed the correct way? It's not uncommon for people to aim their VHF/UHF antenna backwards. The little end should point towards the towers. Just making sure.
It's stange that you aren't getting any signal at all from ABC, since they are currently the only station broadcasting at full power. Over here in Harrison I get a 85+ signal from ABC, CBS, NBC, and PBS, so I'd think you should be able to do the same in Middle Valley, unless you are behind a huge hill or something. If all else fails I'd give a preamp a try just to see what happens. I'd try to get a good one like a channel master or something, though, as Radio Shack preamps can many times cause more harm than good.
TBN is Trinity Broadcasting Network, they're located on Lookout Mtn.. I never watch it, but I do get a decent signal from them.
As for your decoder, I think it will say HD for everything, even though as you pointed out that is not the case. Anything with the black side bars is not HD, but just upconverted. Most primetime shows are now in HD, and that should automatically stretch to 16:9 when they come on.
As for FOX, I think our only hope is that they get bought out by a decent company. Their current owner, Pegasus, is going through all sorts of financial problems, so I wouldn't expect them to spend any money for quite some time.
The good news is that WFLI WB53 just got bought by Meredith Corp., which actually has money, so hopefully they'll be going online sometime in the near future.