Originally Posted by SeanGAR

I've replaced a few touchpads over the year on Dells but the other things going on make me think that something else is awry with your computer. Have you done thorough antivirus and spyware scans?

One way to discount hardware is to boot a live CD from one of the Linux distributions ... Ubuntu is a good one to try. If you run a live cd, you don't have to install it so you can run linux from the cd itself. If the live cd runs fine and you dont have any errors when using the trackpad under linux, it is likely a software driver/virus/spyware issue rather than a hardware issue.

Also you may be able to disable the trackpad in the BIOS and use an external mouse.