I have Windows XP Pro on a IBM/Lenovo Thinkpad T60 and occaisionally the UI is jumpy. This is all facets of the UI, including mouse cursor, video, and audio. I can't define when this starts, but logging off or restarting the computer fixes the problem.
It sounds like you've got something running that's using up a lot of resources and when you log off it clears them so when you log back on the UI is normal.
Start with a malware scan using something like Ad Aware and also a full virus scan might be in order too.
Next, and more manual, is to check what applications and services run on startup. When you get the problem close each one in turn (apart from the basic OS ones of course!) and see if that cures the problem. If you close one and the UI returns to normal you've found your culprit.
Then either uninstall that application (if you can), or if you can't make sure you have the latest version installed.