Virus blocking almost everything, bluescreen appearing

Hi,

I have a problem with my computer and it is quite urgent because the pc isn't mine. I have an MSI WIND NOTEBOOK, some days ago I think I downloaded a program containing a virus which often redirected me on different other sites while surfing in the internet.
I couldn't delete it with my antivirus programs (I installed 5 in total), and today it slowed down my pc, so I restarted it. I realize now that it was what the virus wanted, because now I cannot access windows at all. All I can access is F keys.
Every time when I boot my pc, it shows me just the first logo of windows and then for a second the bluescreen, then it restarts again.
I tried to reboot it in the safe mode etc., but nȯne of these modes doesn't work. I also tried to return to the last normally working configuration but it is blocked, too. Besides, this pc doesn't have a place for cd, so all I can use is a usb key.
I don't want to restore the initial data and to lose all the information stored on this pc.
Can anyone help me with ideas how to get my computer in normal mode again?

These are links to Anti-virus vendors that offer free LiveCD or Rescue CD files that are used to boot from for repair of unbootable and damaged systems, rescue data, scan the system for virus infections. Burn it as an image to a disk to get a bootable CD. All (except Avira) are in the ISO Image file format. Avira uses an EXE that has built-in CD burning capability.

• Avira AntiVir Rescue System - Tutorial for Avira Rescue CD.
  If you encounter problems running the Rescue Disk, you can get further assistance at the Avira Support Forum.
  
• Dr Web LiveCD. Be sure to print out and follow the instructions provided in the User Manual.
  
• F-Secure Rescue CD - Rescue CD 3.01 released.
  Video: How to Remove Malware with F-Secure Rescue CD
  If you encounter problems running the Rescue CD, you can get further assistance at the F-Secure Support Forum.
  
• BitDefender LiveCD - Index of /rescue_cd
  If you encounter problems running the Rescue CD, you can get further assistance at the BitDefender Support Forum.
  
• Kaspersky RescueDisk - Index of /devbuilds/RescueDisk/
  If you encounter problems running the RescueDisk, you can get further assistance at the Kaspersky Support Forum.
  

If you are not sure how to burn an image, please read How to write a CD/DVD image or ISO. If you need a FREE utility to burn the ISO image, download and use ImgBurn.

Let me know how it goes.

Thank you for the information, though I cannot put a cd in my pc, it is a small notebook and has only usb ports. Are there any programs with whom the pc can be booted from a usb key?

I have another problem with another pc, I got a similar virus some time ago, so when the pc was working, it resulted in a blue screen all the time, though later the virus ceased his existence, but it must have erased or blocked something, because now I cannot get the access to the internet, I can't open programs like utorrent, window media player classic, windows support center... When I try to do it, for utorrent I receve a message which says something like "WSA(S) startup failed or you have the incorrect version of winsock installed". I tried to scan my pc with Avira Antivir rescue cd, it scanned normally and found some trojans, but when I wanted to configure it to erase all the viruses he had found, it froze completely and nȯne of the buttons responded. Can you help me with this?

Sorry, I didn't read the instruction carefully, so I didn't put the option to actually repair malwares, so I'll try it. Though the problem with the other pc is essential.

I tried to scan my pc with the Avira rescue cd, so it renamed the trojans it had found, but after scanning it with antivirus, it didn't erase them. Was it because I didn't save the scan results?

Not sure.

Can your computer boot fine yet?

So I managed to boot my pc from a usb key (the one which rebooted every time I switched it on, not allowing to work even in safe mode), the avira antivir found 2 trojans and renamed them, though when I tried to reboot it normally, there were no changes, it just shows windows logo, the blue screen for 1 second and then it reboots. Why didn't it work?

It may be a hardware issue.

Please read the following: set up Memtest, then download Memtest86+ from here.

I tried to put memtest on my usb with the help of unetbootin, but when I wanted to run the test on the damaged pc, it didn't do anything. Maybe I didn't correctly format my usb, that's all I can think of.

I tried to download memtest EXE file for usb key, but when I try to open it, it just shows black window for a second and then nothing else happens.

So you booted from the disc, and it showed a blank screen?

I booted from a usb key, it counts seconds till the beginning of memtest, but it doesn't begin, so it starts counting seconds again and again.

Weird...

I am going to look the situation over and get back to you.