Is this a virus? I cant search for a anti virus online without IE closing!?

I had a anti virus pop up that I didn't want and I thought I had deleted everything off my computer. But when I search for avg or spyware terminator on IE or Fire Fox they close and dont even give me the option to download. How can I fix this I NEED HELP!!! It is driving me crazy. Also I did a search on my computer to make sure all the files was gone and they are so I believe. The programs that were on my computer and that I took off was antivirus 2009 and system guard 2009 Because they were popping up for me to purchase and I didnt want to. Please help