choppy video in all programs/websites A fault of Quicktime ?

I have restored my image of Vista a few times lately because I am trying to
watch video from TV websites (abc, nbc) if I turn off all areo stuff (best
performance setting) it is much better but not a solution...I think i am
seeing a big degradation after installing quicktime, anybody noticing this?
I haven't installed it this time around and I am hesitant to do it, but I
know i am going to need it at some point.

I am getting more and more unhappier with Vista, it seems it is too easy to
gunk up and slow down after installing programs. i never did so many restores
with XP the last 5 years compared to the last 10 months of Vista.

any valid quicktime players/plugins that aren't as monstrous as
itunes/quicktime install?