Many performance issues on Windows XP

[joevenzon]

The full-screen and resolution switching problems on windows will hopefully be addressed with the next release.

I believe the main reason for the slow performance is your graphics card. Disable shadows in the options->display->advanced tab and that should speed things up. You can also disable shaders, which will speed things up even more at the expense of visual quality. Let me know if this helps; I'm curious.