Hi, my computer just freezes when I turn it on. It loads the wallpaper after I click on the login, but it won't go past that. For some background, I had several trojans on this computer which I got rid of but there were still problems with the computer changing my wallpaper to some bogus message about my computer being infected and that i needed to install some antivirus. So I downloaded the professional version of avast and rebooted my computer. When it came to, it at first loaded all of the icons but they weren't working, then it won't even load the icons or the start bar. Should I just remove the hard drive and salvage the data, or remove the antivirus or just cut my losses and reformat my hard drive after of course salvaging my data

Try running Avast from Safe Mode (tap F8 key whilst booting).

some other bloke...