If I reset the BIOS to factory default (assuming I can figure out how!), what will the effect be on my data? Do I lose everything and effectively have a new computer with nothing installed, or does it just tweak stuff in the background?

The reason I'm considering doing this is that my mouse is playing up. The right button acts like a right, but the left alternates between doing what it should and doing what the right button should. The only solution I've found online for this is resetting the BIOS, and I'm wondering if it's worth it - or will the mouse, and thus the entire computer, become completely unusable if I don't?

Of course, if anyone has an easier solution for the mouse issue, I'm all ears. To reiterate: the right click acts as it should; the left alternates between left and right actions, so just changing the button settings doesn't help.

I'm no expert on this sort of thing, but personally I would try replacing the mouse or if possible try using a different one on your computer. This sounds similar to issues I've had before, and the solution was to get a new mouse because the other was either worn out or faulty. You probably shouldn't mess with the bios unless you know what you're doing, and I doubt the factory reset would help in your case anyway. If you have any other devices that you could test the mouse on I would do that, or like I said before if you can test a different mouse on your computer try that too because I think it's the mouse itself that is the problem.

If you did do the bios reset it shouldn't cause any problems to your data, though I would only try that as a last resort if nothing else works.

A worn-out or faulty mouse can do a lot of strange things. I've had at least two that tended to suddenly act as if they were not connected, or kept giving the USB connected/disconnected sounds. Or just stop working in the middle of a session even if the mouse light still glows. They would also refuse to work in one USB port but work fine in another (I'm suspecting a couple of the laptop's USB ports are a bit faulty too, because I've had similar connection issues with other USB devices).

Before you do anything drastically, you may want to check the mouse settings, try a different USB port, possibly check/reinstall mouse drivers, and if all else fails, try another mouse.

Thanks, guys. You were right: I should have tried the simple stuff first instead of assuming it wouldn't work for me because it hadn't worked for somebody else. I've got a different mouse in a different USB port, and it seems to be behaving itself. Funny thing is, the new mouse is the one I first tried to install when I got this computer, and the computer refused to recognize it. Computers be weird.