Scratching my head...

Before anyone begins to unload on me, I have already checked out the READ & RUN ME FIRST thread. No I haven't run it yet, because I saw in one of the threads I was reading that SP2 could cause additional problems. I already had SP2 loaded before encountering this, so what I'm wanting to know is if I need to take any steps above and beyond what was in the READ forum thread before beginning those actions?

I am sure that I've picked up some kind of virus, because I got a link from a friend a few days back with a link to some pics. I didn't suspect anything because they've sent me similar links in the past. So when it cam up in my Trillian IM box, I clicked on it. Nothing came up, and I instantly thought something wasn't kosher. Two days later I get two separate IM's from people in my list saying they had tried to view the pics on a link I had sent them (which I know I hadn't because I hadn't been in contact with those two particular people for a few weeks). So I'm going to follow the steps I've found here (and thanks to all the forum threads. I am far from a computer guru). As I said, I just need to know if there's additional steps I need to take regarding SP2 before beginning.

Thanks in advance.