Acer Aspire 9300 issues (+REP)

Having great problems with my Acer Aspire 9300 laptop.

Firstly, if I load up a certain game (never had any trouble on any other system with said game), the computer screen goes off. The same occasionally happens with Media Center. There is still activity in the computer, the power remains on still, and to my knowledge, so does the sound. When I came to reboot after this today, it wouldnt boot to the welcome screen. Shut the thing down manually, then tried doing Startup repair. After 2 cycles it worked.

I also get this if I pick the laptop up sometimes. However, when this happens, the computer shuts down. On next boot-up, there isnt a problem.

Another small problem is that the webcam keeps flashing up for new drivers if the lid moves much (IE someone knocking it as they walk past)

Also, IE7 keeps freezing up sometimes, often while loading a page on HxF. If I have more than 2 windows open, if I click a link on the working window or refresh, it freezes up that window too.

Another problem (Wow, I have a lot of problems with this thing), is that occasionally, Firefox will reset and go back to the Welcome to Firefox thing, with the original skin.

The left mouse button is sometimes unresponsive. It will function, but not make a "click" as it does it. It just feels a bit stuck to me.

And finally, Windows Update. Everytime I try and run it, it fills my hard drive, no matter what the size of the update. It once filled 2.5Gb with something like 12 updates.

The computer is just over 2 years old, running Windows Vista Premium.

I'll gladly provide any other specs if you need me to. I'm hoping this'll be a fairly easy fix, I'm probably wrong though.

Anyone that can help me will get +REP where possible.

Any solutions that will stop me doing this :eusa_wall will help

OK, another update. Last night the computer froze up while I was using Habbo and iTunes. The screen went off, I had to boot down manually.

Came to boot up just now, Startup Repair, again.

It is taking a while, with the message

Checking disk for errors.

Is my computer dying? or is it dead already?

I am REALLY desperate for help now. I need my laptop for everything.

EDIT: It now wont boot into windows at all!!!!!!!!!!!!!