ppinard,
I might suggest making sure your drivers are updated. Are they, or is a new version available? If so, many of these issues may be corrected.
The resolution is fixable with the television. I suggest you use the Just Scan feature on your HDMI input, and rename your inputs to PC. It will change the scaling. You should also be able to use AutoMotion Plus technology by doing that as well, giving you a better text.
Keep me posted!
--HDTech
I bought the LN40A650 for use as a computer monitor, and have been quite pleased so far with it, however i have a few issues
I have it plugged into the HDMI / DVI port #2 using an HDMI cable hooked to a DVI to HDMI converter on the PC and i have a component stereo cable to standard headphone jack cable hooked into the PCs sound card - an onboard sound card, the video card is a BFG nvidia GTX280
Firstly the sound isn't working on that input, i verified that the cable is good using the side inputs and an ipod and the sound card is good using headphones - but every few hours i will hear a crackle from the speakers
Secondly i have not been able to get the 120hz true motion to work with the hdmi/DVI connection on port 2 - i like my games to look very high resolution, and port 2 is the only one that seems to provide 1-1 pixel mapping and crystal clear text, if i plug it into hdmi port 1, i get the 120hz effect, but things are scaled and i cant get the super clear text i could with port 2
i dont so much care about the sound as i want to get a good sound system anyway, but i would really like to be able to get the clear 1-1 pixel mapping without any bleed that i get with port 2 to use 120hz conversion, so what resolutions or scaling settings do i need to use?

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic