Problem with startup

I start up crossfire, click the OK thing and then the hackshield thing comes up. It goes away, and then I hear my computer slowing down (fan slows down). Then, nothing happens from there on, and my computer lags for like 10 mins.

I using XP but I cant respond to ur comments cus i have to go to bed

Toshiba Satellite.

PS: It worked up untill today