i'd agree with above. crt might give you the best picture for your old content, but I think anything getting upscaled well and displayed on a HD projector is a better way to go. we always change plans, and buying a BD player alos allows you to buy your new movies on a better format and enjoy them even more. you don't have to replace your old stuff, but you shouldn't limit your new content either.
that and once you go digital, you might as well go 1080p. you might not get 'higher resolution' technically, but you'll be less likely to see pixel structure. I've never heard of a SD signal looking better at 720p. it's either native, or upscaled. and once it's upscaled, might as well go all the way.
Displays: Samsung PN64F8500/JVC X35
AVR: Pioneer VSX-1130K, 7.1/5.1.2 audio
Sources: HTPC(Enby), PS3, XBOX360, Wii
Control: Harmony One