How do you wipe a PC clean?

I want to wipe my computer clean as it is messing up with virus and the like. I don’t have any programs aside from Zune (my MP3 launcher) that I personally installed on it. Also, I’ve had it rebooted by a tech professional some time ago, I kept getting the "This copy of windows is not genuine" error. How can I wipe my computer clean to start over, and what, if anything, would I miss?

PC- HP Pavillion a1440n
Memory- 2 G
Monitor- Samsung 19" Syncmaster 932BW
Graphics Card- ATI VisionTek X1300 512 MB
OS- Dual Xp\Vista home Premium ( have been using Vista only since I upgraded, haven’t used XP os in 2 years)

I always keep my pc clean of dust and regulary use Window Washer to keep the system clean.

Sequence of events:

3 months ago… Aquired hijacking virus along with a quarter of the screen size popup ad when surfing and also a virus that replaced every ad banner on every web site with ViMax male enhancement ads.

Tried repeated attempts with Spybot Search and Destroy which always worked for me for this kind of thing for years. It never found anything. Yes I kept it updated.

Tried several other popular freeware similar to spybot with failed attempts. No viruses were ever detected. I knew I had a bada$s virus at this point.

One Microsoft recommended free removal program was from K7 Computing. No luck there either, though I suspected this to be a troublesome program after I removed it from my program files like i did with every other program that didn’t work for me. Every so often afterwards, the K7 icon would show up on my desktop or on my Rocket Dock even after I deleted the icon.

2 Months ago:
I began to use software to clean my registry. It worked for its purpoe but never found or deleted my viruses.

1 month ago:
I began to wake up in the morning and the PC would be shut down even though I didn’t do it and I didn’t have it schedueled to do so. I thought it may have been my 3am automatic updates but quickly didmissed that because there weren’t always updates and it would always restart if there were. Now as time progressed, throughout the next few weeks the computer was hesitant to load up when I hit the power button. When this happened it would power off instantly when I touched the power button unlike normally a have to hold it for a few seconds. After a few attempts it would eventually load up.

The fan began to run louder than ever, so I attributed the non-startups as a result of overheating. I removed the heatsink and fan, dusted it back to new and added new silver thermal compound between the heatsink and Intel processor after cleaning the old stuff off. Now it was quiet as the day i bought the PC. No luck with the normal startups though. I had suspected the virus all along.

I finally found a solution to the virus. It was a program called Malwarebytes. It came recommended in forums and it worked! It found several viruses and trojans and removed them all. PC and internet were all back to normal and I was happy as could be…

The next morning after the fix I awoke to see an unfamiliar desktop which looked like a basic desktop when you first install windows. The recycling bin and two program icons which I don’t remember where the only thing there besides the basic vista background and the task bar…
In the taskbar a little notice popped up. It said I was logged onto a temporary account as my normal administrator account could not be loaded. I had left the PC on in its normal administrator account the night before. I had done nothing.
So I immediately checked to see if my files were still around and they were through Explorer. Turned off the power and figured on backing everything up when I got back from work. I know I’m an idiot for not doing it in the last 3 months.
Anyways, since that morning my PC has never come back on. I can power it up and sometimes I even hear the windows loading sounds through the speakers but not always. I know the pc recognizes devices because if I hear the loading sounds I can press the logoff button on my wireless keyboard and I hear the sound it makes as it logs off. Now it doesn’t always "boot up" but I know when it does because I’ll either A;hear the sounds B; unplug the monitor cable from the pc and the monitor recognizes it has lost signal or C; when I hit the power button I have to hold it as opposed to it shutting off immediately as I have described above.

I have tested the monitor with my laptop and it works fine. I have placed my original video card back in the pc and nothing different. So I’m sure the video card is not the problem. I have tested the two memory sticks individually and in different slots with no results. My most recent test was to Map Network Drives and try to access my pc through the laptop to recover the files. It recognizes my pc but says I’m not logged onto the Administraor account. The problem there is the last time I seen anything it said I was was logged onto temp account of some sort and I don’t know what it is called if anything at all.
No luck with anything.

So if anybody has a solution as to how I can recover my files before I take it to a specialist, please share your wisdom. Would I have better luck trying to connect to the pc directly with a cable? Or if this has happened to anyone else and knows what the actual issue here is, PLEASE tell me.

Sorry for the sup
Sorry for the super long post, but I wanted to be as thorough as possible. I really don’t think I have any more information to give, but if there are any questions, I’ll be checking the post regularly.

Thank You,
Drexyl

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