My plan for the kids media/hangout room is for the kids to have an area of their own and that is comfortable enough for their "old man" to hang out too.
This room will have a 50 to 56 inch TV, 5.1 surround system, dvd player, and some type of game system (either PS2 or 3, Wii, or Xbox) for the kids entertainment. My thinking for this room is to have a room I to can use to watch "regular" TV such as news and such without firing up the pj and to have a room that the kids and their friend can use without concern or fear of messing up or destroying the HT.
I have tried to think of all cabling issues and have to this point run from the "command center" in the "main theater" one HDMI, one set of composite with stereo audio, one set of component with stereo audio, and cat 5. My plan at this point is to have the Denon 4308CI at the nerve center. This handy piece of equipment has 2 HDMI outs and a component out for zone two. This is the main reason why I have done run the cable the way I have. Theoretically the TV in the media room will be able to display what ever is showing in the main HT or we will be able to watch any source I have connected to the Denon. I then ran the composite for the ability to hook up to the TV 2 out on the Dish HD receiver I will be installing in the HT.
Hopefully this all makes sense and there are no holes in my thought process. Especially since I just finished running the cables yesterday!
Here are some pics.

Low voltage boxes with the cables hanging out.

Cable clip in use. The ones I purchased had three dividers creating four sections for cables. What I did was to use side cutters and remove the three plastic pieces to create one big cradle for my cables. If you look close you can see zip ties. I used zip ties to bundle the cables together to make them easier to handle and run.
I considered using conduit but for this particular run most of the run is going to be in an area that is to remain unfinished so I will have access to the cable if I need to run different or more cables in the future.

Picture showing frame out for the DIY audio rack

Close up showing cables for kids room. The area behind where the furnace, water heater, and water softener are located will remain unfinished except for the wall of the theater.
Regards,
RTROSE