Let me explain why you were crashing to the desktop. Basically, your computer was taking too long to preload the textures after connecting to the arena. By making them smaller, it should reduce the preload time.
You might consider a defrag of the hard drive as well. Also check to see if you are having other resource issues. Make sure the CPU usage in the 'Processes' tab of the Task Manager is showing 0 to 1 percent usage and no higher.
For right now, I am going to close this as fixed.
