My computer is messed up (virus,malware,something etc>?

Hey, i recently got malware called anti virus xp 2008 and i simply got rid of it by running in safe mode then running AVG. Since I did this i have been having problem. My internet is much slower and when my windows xp loads up it often freezes and take a couple of tries(like3-4) to get working without freezing. Furthermore when I'm using a search engine link Google and when a click on the websites it often redirects me to various websites like findstuff.com or searchsomething.com which is not related with what I'm searching for. I thought i got some other virus so I ran AVG and spyware terminator but they found nothing. Do you have any clue what is going on and how to fix it. All input will be appreciated. Thanks for your help.