Usually if your video card is the culprit, your whole system will freeze for a few seconds. You said the desktop was functional, so (to me) this would put the video card a little lower on the list..
It is possible, though, that the video card isn't very powerful. Since you hadn't posted your specs, it's hard to know. Windows XP really pumps up the quality settings by default, which can cause a serious slow-down on a lower-end card. The good news is that it's easy to disable some of the features.
Try this:
1. Click Start, Control Panel.
2. If you see "Performance and Maintenance" click it. If not, skip to 3.
3. Double-Click "System"
4. Click the "Advanced" tab
5. In the Performance section, click {Settings}
6. Choose "Adjust for best performance"
7. If you want to keep the XP look, check the following options:
(Bottom) "Use visual styles on windows and buttons"
(2nd from bottom) "Use common tasks in folders"
(5th from bottom) "Smooth edges of screen fonts"
All others should be un-checked
8. Click {OK} twice.
Now, see if you still have the problem. If so, you can revert the settings back by following steps 1 thru 5 and choosing "Let windows choose what's best for my computer". Also, you can experiment with this section to tweak it just how you want it.
Be sure to reply back with your results!
Good luck!