I have a G61 series HP laptop, which I have been using for about 3 years now. Basically, my laptop has been having [overheating] issues for (I think) around 9 months now, and I did clean its air vents 3 times during these months when the problem started. It's not really a gaming laptop, but I still pretty much used it for 2 high-end MMO's at medium to lowest settings, other than just web browsing, video streaming, internet messaging, online calling. And then, during the last 1.5 months, I was getting some "black screen" just by streaming even the simplest of [YouTube] videos, running more than 2 programs (with Skype always open, MSN, or Firefox/Chrome, etc.), browsing a page for too long (Facebook, YouTube, etc.). When this happens, I just forcefully turn off my computer, and wait for a couple minutes. And when I turn it back on, I always select "Start Windows normally". *Knowing about my "black screen" issue, my computer activities became minimal with only Skype open, some light browsing as much as possible, and/or MSN.
Judging by what I've said so far, I'm quite careless and impatient in taking care of my laptop, don't you think?

So, what happened some hours ago was that I got a black screen, turned off the computer, and waited for a bit. I turned it back on, and basically got stuck at the "Starting Windows" screen. I think this happened before, but I would just reboot again and it'll be fine. Unfortunately, it didn't work this time, so I tried to repair at the 3rd reboot, but it was taking awhile that my laptop would just turn off. I tried to reboot the 4th time, waited at the "Starting Windows" screen, then it turned off again. I decided to leave it be for about an hour, came back to try again only to experience the same thing. I did notice it getting warm that quickly when I tried a couple more, even when I tried testing my hard drive (It didn't finish, because it turned off) and memory.
I don't think I have accepted yet, that it might be hopeless to fix this eventhough it probably is. I would like to know what could be the specific problem(s) of my laptop? If you think there's still hope, I'd appreciate some detailed advice on how to make my laptop be useable again.

*EDIT, added info
Edited by xsarah, 03 January 2013 - 12:22 PM.