For any TV that you may want to buy (or anything audio visual) I would do a comparison at
www.avsforum.comAnd before you go buying any component, dvi or HDMI cables i would goto
www.monoprice.com-i don't think they have cables for 360 or Wii, but lots of quality yet cheap cables for the rest of your entertainment center.
If you are looking for value priced HDTV's, I have a 32" 720p Olevia that i got over 2yrs ago for $500. no complaints so far.
Another value brand that seemed to be pretty good was Westinghouse.
I know a few people with Vizio's and they are split about 50/50 on decent and crap as far as personal reviews.
Most of your other questions have already been answered, but a few things that I would recommend you pay attention to are:
1) Number of HDMI/DVI/VGA/Component input/output connectors (2/1/1/2 would be a good configuration)
you want something that is gonna fit your needs now, and can expand for future needs.
(Wii. X360, PS3, dedicated DVD player, Cable/satellite box, computer, etc. etc.)
2) Black Levels (ie 10,000:1 is what my TV has, looks good)
3) Refresh rate (the lower the number the better, especially for gaming - 5ms or less if possible)
4) Internal HD Tuner (can catch over the air signals & you won't need an external cable box)
I'm sure there are more things to look for without making this all too complicated, so I'll update this with more as I think of them.