SL Boot time

Having just upgraded from Leopard to Snow Leopard, I'm noticing a weird new problem. Since the installation, my desktop freezes for about three minutes after boot-up. The boot time takes the normal amount of time, but then I can't select anything at all for about three minutes. The cursor moves freely, but nothing at all can be selected. After about three minutes, everything works normally. Anyone else have this issue,or have any idea how to solve it? BTW-I downloaded 10.61 update. Also, this is a new refurbished computer with not much of the way of software loaded yet, so I don't think there's a bunch of conflicts happening. Thanks,

Kirt