Out of Control Scrolling in Windows Vista


I am having a major problem with my screen suddenly scrolling, blinking, the little chime constantly ringing, and sometimes beeping. I have searched the forum and didn't find any answers. I have also tried defragmenting, chkdisk, scanning with AVG Free 9.0, but none of them work long-term. I tried using the Recovery Disk download, but it turned out that my version of Vista already has it, and Recovery Repair didn't stop it. I've tried System Restore, but the problem started a long time ago (I don't remember exactly when, but I've consistently had this problem for a couple of months. It doesn't always happen and I can temporarily stop it by pressing Ctrl and another key, but it doesn't work long-term. Every time I start the computer the Windows Memory Diagnostics window pops up, but it never finds a problem.

I'm thinking of backing up my files and reinstalling Vista, but I'm not sure if that would help. Has anyone else had this problem? What's going on?

(*phew* I can't believe I was able to type the whole post without it shaking up on me.)
Out of curiosity, have you try to use an other mouse?

I had similar problem before and it was the Logitech Keyboard/Mouse Combo (wireless USB) which forced that problem on one computer and on an other the USB Nice Laser Mouse (cable)!
Like all the

Yeah, the computer started scrolling while I was typing. To answer the above questions, I don't have a mouse because it's a laptop and Safe Mode initially worked but then it started up again. I'm backing up my files right now while everything's functioning okay just in case. I'm wondering if it's a hardware problem? The computer's a Dell Inspiron and it's only 3 years old. But I'm having someone look at tonight (luckily it's for free) so maybe I'll find out then.
May cleaning the Laptop from inside would do something?!

I don't thing it's software, I do believe it's a hardware problem may with Mouse/Touchpad or Keyboard, even Dust on MB could force that action!