First of all I know that this laptop has viruses on it causing the problem - it lets me log in but then logs me straight out again. I think it's to do with userinit .exe and wsaupdater.exe files but when I use recovery mode to correct these I then have to reboot and I think the virus(es) undo my work. So how do I get out of this loop and get to the desktop so that I can scan and remove the virus(es).
Restart System and keep tapping F8, and select the option "Use Last good known configuartion" (the option is something on those lines.) and press enter. Your system may pause there for a few seconds and then Windows should load. Now try logging into the system.