I have a Dell Inspiron 5000 with SuSE 7.2 (yeah I know, old, but hey it's an old laptop). The laptop can use either a PS/2 mouse to control the cursor or the built-in trackpad, but not both at once. When I use the PS/2 mouse, it works fine. But when I boot up without the mouse and try to use the trackpad, the X cursor is very erratic, jumping back to the lower left corner and moving around randomly while registering all kinds of mouse clicks (1, 2, and 3rd buttons). At first I thought the problem was in the hardware, but when I downloaded Knoppix and booted from that, my cursor worked fine from the trackpad. So it must be a software issue on SuSE. Does anyone have any ideas on how to go about finding the problem and fixing it?
Thanks,
Ben

Jumpy cursor usually means the wrong mouse driver in X. Your pad should be a ps/2 (/dev/psaux) mouse, but the Protocol is probably wrong. Have a look in your /etc/X11/XF86Config and see which one you're currently using.

Thanks mcleodnine, that did the trick. Apparently I had changed the proto to IMPS/2 a while ago and hadn't used the trackpad for a while so I didn't notice.