Sometimes when I'm in the game, it lags.. well it's always laaggiiingggg. But when I'm in a new place, my character stops responding to my mouse clicks. It's really wierd. I tried turning down the settings, but it didn't help. Specs:

P4 1.5 GHz
256MB RAM
nVIDIA Riva TNT 2 M64

I know that I have a ...