This is a pretty simple debate between LCD and Plasma. If you have control over the light level in the room get a plasma as they have far better pictures than LCDs, although LCDs are getting better. What I mean by light level is covering windows, you can use it with the lights off/dimmed etc...
The issue of burn in on Plasmas is basically a moot one as is motion blur on LCDs. These were problems with earlier generations of these displays that have been overcome. Plasmas have added pixel shift to combat the problem which is very effective while LCDs have upped their refresh rates to combat their own problem.
If you get the latest generation of either set you will be good for sure, but even if you get the last generation of either you will be okay with both problems. 120Hz refresh rate is not needed to make motion blur unnoticeable (except in a side by side comparison). Last gen plasma models have pixel shift too.
So don't worry, choose your set based on your lighting, both will do a good job for you if you get a quality set.
For brand recommendations:
Plasmas: Pioneer (far more pricey) or Panasonic
LCDs: Sharp, Toshiba, Sony (many people seem to like these, I don't)