Track Pad or keyboard?

I have a iMac with a magic track pad, today I got home and started using my iMac and it seems like a click is held down on either the keyboard or trackpad as things are selected and "clicked on" without me doing anything. Any trouble shooting suggestions?

Jon

Shut down your Mac
Turn off the trackpad, or take its batteries out
If you can use any USB mouse plug that in to the Mac and start it up

That way you should be able to tell if the Trackpad is at fault or the Mac or Keyboard.