Blender 2.62 Mac OS X lagging

Hello everyone,

I have been using Blender 2.62 for 1month now, but suddenly it has begun to lag extremely, i can hardly open the menus or anything. I have tried to reinstall without any luck.

My system:
Mac OS X 10.7.3
2.4GHz Core 2 Duo
8GB Ram

As mentioned before it has been running very smooth, now its impossible to use.

Any hints on what i can do?