The Samsung plasma FPT5084 is really nice and folks at AVS love it. I also have a Samsung plasma and love it. I would say keep it.

But don't get the $389 extended warranty. It's useless for most of the case. I believe Samsung warranty for this model is 2 years so that's plenty of time.

The panel life is 60.000 hours so if you watch 8-12 hours a day (which is a lot for most people), it will last for 15-20 years by my calculation.

If you want a simple Home Theater in a Box (HTIB), consider Onkyo HT-SR800 7.1 system for around $400. It has plenty of power for your current need. But if you plan to get a Blu-ray player down the road, the Onkyo (and most HTIB) does not decode High Definition audio formats over HDMI but it has 7.1 multi ch analog inputs to enjoy the hi-def audio.

If you want HTIB that has HDMI audio processing, you can search for Onkyo HT-SP908 which is around $700-800.