Have no fear! You purchased one of the latest generation DLP TV's. The HD2+ & HD3 chips were released at the same time so one isn't necessarily newer than the other. Your chip actually offers better contrast (so deeper blacks) than the HD3. For watching DVD content, there's nothing better out there right now (in my opinion). The audio/video synching problem could be due to the video processing that is occuring inside the TV. Try turning off the Dnie on the TV (this can be done using the menu) and see if that helps.
Just got done reading an article about DLP's. I recently purchased the Samsung HL-P5685W and am a little concerned that I should have waited for the newer chip set(HD3 or xHD3). I assume mine is the HD2+. I read an awful lot of reviews before buying and felt comfortable that I was not wasting my money. Spent almost 5,000 dollars for the set, Samsung HDTV receiver, dvi cables, and also the extended warranty. It is still not to late to return the set. I still have 2 weeks left to return it. Any recommendations?
Also, voice does not always correspond with picture. (lips move before sound etc.) Any thoughts of what this might be?
Any help would be appreciated.

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic