Jumpy scrolling

I recently reformatted / restored my computer, Its a Dell P4 2 gig, 640 Megs ram, Windows XP
Now, when I am scrolling down a page on the internet
for example (Use the Grab scroll bar on the right hand side of the screen) the text and pictures do not slide down smoothly they jump at maybe 3 to 5 lines at a time. It's very irratating.

I have 2 other pc's and they don't do this, They go down smoothly as if it's a continuos page rolling by a window. (I hope thats a good description) and I am pretty sure the Dell didn't do it before I had to reformat. So I'm sure it's something in the settings.

I have tried 3 things so far,

1. Went to control panel and adjusted my mouse wheel settings
No imporvement.

2. In Internet Explorer clicked on tools then Internet options then
the advanced tab clicked and unclicked "Use smooth scrolling"
No Improvement

:argue:
3. Called Dell Tech support, Very weak so to
speak. To sum it up.... I don't know sir

I hope one of you all knows a lil trick or something because this
is sure deterring from the enjoyment of our new PC

Thanks for any help or efforts.