Virus started as XP Total Security now Window

Hello,





I recently inadvertently let in a virus that called itself XP Total Security. I am using Windows XP and was using Microsoft Security Essentials for Protection.OOPS!
After using another computer to search Bleeping Computer Forums, I managed to download RKill and Malwarebytes. I have ran both several times. Malwarebytes seems to remove the virus but when I re-boot it is back but with a different name. Now it is Windows Security Alerts. It has also hijacked by browser and will not let me do normal searches in my browser(Firefox) without re-directing to various other sites. I'm not sure what else to try. Now whatever the virus is - it is affecting non-web usage. While working on documents in Word or Excel, my computer will freeze and the only way I can move is to power down and then power back up.

I have also now tried Spybot and AVG. Even though they say they find trojans to remove - I am still having massive problems. Most of the time I can not log onto the internet and when I try to use System Restore - it either doesn't open or I get a pop up box that says System Recovery will not help me and then it exits. Please can anyone help?