Trojandownloader.xs?

ok this is my 3rd question on the topic first one led me to spybot-SD and then i had errors so it led me to getting smitfraudfix so i went to the site got the program 'ran' and then hit scan, afterwards i started in safemode and cleaned it saying yes to registry clean, then restarted in normal mode, when my computer starts off it loads AVG because it does it automaticaly but when i try to run Spybot-SD it freezes up the whole thing, nothing works except CTR+ALT+DEL then restarting from there, i fear i have just gotten my computer into some deeper sh!t, what should i do, and btw it freezes if i open anything, not just spybot, im on a different computer right now