Dual-boot? I'm pretty sure further reducing hard drive space wouldn't be all that wise...yeah, it's likely to be more an issue of RAM, graphics card, and processor speed. Probably time for a full-system upgrade, sad to say. Alternately, if you want to try and squeeze out a tiny bit more power, you could boot in safe mode, which will turn off all unnecessary programs, including things like resource-hogging display programs. That should free up some resources. To get into safe mode, restart the computer and immediately start hammering on F8 (probably). If you get to the login screen, try again.