Help With Major Computer Issues (freezing, virus, black screen of death etc

[Irishlass2]

Hi Everyone,
I hope this is the correct place to post this question. I am having a heck of a time with my computer (numerous problems) and I am hoping someone can help. The problem is beyond my knowledge. My system is Windows Vista Home Premium 32-Bit, on a Dell Inspiron 1525 2.00BG RAM. I would like to give you some background before launching into the problems and solution attempts. Last years I had a terrible virus that nearly destroyed my computer. I couldn't get the root kit out. I called Dell and they had someone access my computer remotely--that was the worst thing that I could have ever done. That person crashed my computer and I ended up with the black screen of death and it wouldn't start. I took it to a person who does computers and they were able to eventually remove the virus after having the machine over 2wks, however my hardrive had been compromised and to keep the computer running, he had to remove a sector on my hard rive. It has worked fine ever since, but has the clicking sound and gets hot from time to time. I have it up on corks and it has maintained well, as I have no money to get a new computer. Until a few weeks ago when I started having a myriad of problems. My computer will work fine if you turn it on and just surf the internet. However, the instant I try to run any antivirus it freezes (even in safe-mode). It will also freeze randomly on the internet and if it goes to screen saver, it just goes to black screen and is unresponsive. When I try to use ctrl+alt+delete {even in safe mode} the computer will either go to a black screen or say security option failed. Also, last week my sound icon was missing and I had to go into the registry to delete superfluous keys to restore the icon. I have tried malwarebytes, hitmanpro, and avast and all freeze and cannot work {even in safe mode}. I have run microsoft security cleaner and norton antivirus cleaner and they don't freeze but find nothing. I tried to do a windows update, and it says service is not running. So I went to command prompt and reset the winsock, that still did not fix the windows issue or clt+alt+delete issue, even after being reset. I am missing BITS in the service section, and the documents and settings folder under C drive won't let me access it. I ran microsoft fixit and it found nothing wrong. When I have to manually turn my computer off after freezing it starts back up with either repair and disk check, or I get the black screen of death with flashing cursor and then it will either go to F8 menu on its own or I press it and then it starts. My computer will not shut down on its own nor stay off unless I manually turn it off. Clearly there is something wrong--probably a virus and other things. Can anyone please walk me through this.
Thanks for everything,
K.

[BigPaw]

Hiya K.

Due to the amount of 'chefs' there have been fixing your computer, and considering the extent of the problems your computer is having, the wisest course of action here would be to reinstall your operating system. Is there a reason you haven't done this already?

The reason I suggest this is because there have been a huge amount of adjustments made to core features of your computer's systems. Even when you get rid of whatever is infecting your computer in whatever quantities, there will then be the very long and laborious task of getting it back to some semblance of functionality.

Truthfully, reinstallation of the operating system has always been a last resort for me. But, in this case, to save you days of hassle that does not come with any guarantee, I would encourage you to make back-ups of your important files and reinstall your operating system.

But, if you really want a fight, and you'll learn a lot about Windows during that fight, then start with Chameleon.

[Irishlass2]

I just don't know how to back up programs etc. I have so much material and I am terrified of loosing it. I am in the middle of traveling constantly, and I can't locate most of my discs to re-install programs etc., and I just am not computer savvy enough to reinstall. I was hoping that I could get rid of any virus at least and then in the near future buy a new laptop.
Thanks