Lee,
Plasma's are fine mate. Go in to a good retailer and get them to hook up a DVD player either by RGB or better still by progressive scan component. If you compare like for like a CRT is always better than LCD or Plasma, but the biggest you can go on that is 36" so you need to make you decision based on what is available.
I'm glad I bought mine as I dithered for about 12 months and had the same worries as you (about picture quality, technology etc), but I did my research and finally bit the bullet. For what I need the screen for my purchase was bang on and I would not of bought anything else.