For the best overall image quality, it has hard to beat a fully tweaked and tuned CRT rear projection set. CRTs have burn in issues though if you use them for gaming or have them set on high brightness and contrast ratios. However, nothing beats the contrast ratio of a CRT RPTV.
DLP would be second, with LCD being third I would say. Both have there ups and downs. DLP and LCD sets need to have the bulb replaced, and CRT sets can have the guns/tubes fail.
Flat panel Plasma is great, but make sure if your going the HDTV route that you don't get one of the lower resolution displays go in the lower price range.
For CRT sets, Mitsubishi, Hitachi and Toshiba seem to get a lot of nods..
For DLP, everyone seems to be going the Samsung or Sony route I think.
Not sure about the LCD sets. I'd rather go DLP because of the lower screen door effect they have over LCD projection sets.