On my TV it's avoidable, but you need to turn off some of the features of my set, like local dimming (which is used for better black levels).
On the subject of LED vs LCD vs Plasma, for game playing and PC input I think that LCD is going to be your best bet. The biggest reasons being burn-in with static elements (Plasma), or possible input lag with an LED. LCD sets always seem to have the least amount of overscan when plugging in PC's in my experience, though that usually can be adjusted through video settings anyway.
As to what to look for in a TV, I'd say if you are going to be watching blu-rays that you want a 1080p set. Might as well get the most out of what you paid for, right? After re-reviewing the TV options in that range, I actually think that
this one looks pretty great. It's got DLNA, which lets you watch things off of your network, it's got a game mode so no input lag, and it's also got a PC input. Made for Midgen™ stamped on the back.