Cursor moves to the bottom-right

Hi everyone!

I downloaded version 7100 a few weeks ago. I love this operating system and would like to stick with it, but I can't fix the cursor problem no matter what I do. It periodically moves to the right bottom of the screen on it's own.

Here are the things I've tried so far:
- turned off "enhance mouse movement" under control panel (suggested on a few forums online)
- turned off laptop trackpad, in case it is reacting to some movement
- switched between between 3 USB ports
- switched to another mouse
- switched mouse pads (dark, non-shiny surface)
- disconnected the mouse from USB port and used the laptop track pad instead
- turned the mouse upside down (such that the little red light was no longer activated, but the cursor still moved on it's own)
- turned off the option to write on screen (I have a tablet laptop)
- checked for new drivers, reinstalled drivers.

I am thinking this may be a software, not mouse problem. The strange thing is, the problem seems to be less frequent for a little bit after I do one of the things above, but then comes back full swing again in a little bit.

Has anyone had this problem before? I would appreciate any suggestions!

-Natasha

P.S. Here is my computer model, just in case: HP tx2610us

Sorry - I am a complete newbie. Does this have something to do with somehow entering the BIOS settings and disabling the trackpad, just as I start up the computer? I tried to find where I could change these settings (F11, F2, etc), but couldn't figure it out.

Yep, I checked there, but my system does not let me change anything in BIOS (besides language, password, a few other things).

I completely uninstalled (rather than updating) all of the "human interface devices" from the Device Manager. In then automatically found them after restarting. So far, so good!!