I can't speak to the specific model you're looking at but I'll address what I can about the other issues.
Plasma is a solid way to go unless it is going in a really bright room. The glass used in plasmas will create a lot of glare. They really work best in darker rooms.
An upscaling DVD isn't a requirement but i would suggest dropping a couple hundred dollars on a combo DVD player/home theater system. The sound system will really create a complete experience. Even if you have to lose a few inches on the TV to get the sound, do it.
Standard def looks decent, until you get used to HD content. It is an absolute travesty not to get HD content for the HD tv. Of course, after you see some HD content on your new tv you'll want as much as you can get.
Good luck.