I just bought myself a brand new HDTV.......As for movies, I always download movies in a XviD format b/c of my modest bandwith (512/128) to save time compared to DLing DVDs.....However, watching XviD on a HDTV is merely useless b/c u lose so much quality......So, I ask what's the recommended software to convert, if possible, XviD to High Definition?

Have you tried watching any of the movies on your new set and just don't like the look of them? I watch XviD and DivX movies on my HD set. Granted, they are not HD but certainly tolerable. I have watched them from the original files (no conversion) and from files converted to full DVD capacity. No difference in pic quality as far as I can see. My guess is that they lose some pic quality (pixelation in dark scenes, etc.) with the drastic compression and there is no way to "put that back in".

...or he can convert the XviD video to DVD format and watch it on an upconverting player in 720p or 1080i.

I have a usb port on my DVd player and can watch videos right off of the flash drive. The player will also upconvert movies from the flash drive.