Did you try adjusting it?
Most of the laptop's have that kind of info in the Manual that comes with them?
The Dell site was not much help:
"Touch Pad or Mouse Problems
Check the touch pad settings
Windows® XP
1. Click the Start button, click Control Panel, and then click Printers and Other Hardware.
2. Click Mouse.
3. Try adjusting the settings. "
Who made the touch pad as there are several makers and their web site might have better info?
You might find this thread helpful
HERE