I've noticed my computer having problems too. One solution that has seemed to reduce the number of times my computer "freezes" is to defragment the hard drive before playing (or after if the defrag is taking too long). This will also help your computer run better when you aren't playing the game.
Our support team can help you but you need to contact us at firstname.lastname@example.org - and when you contact support, please ensure that you give us: ->the account name ->the character name ->your dxdiag file ->as much information about what you encountered as you can, including error messages or screenshots
NEVER send us: ->your password ->your full credit card information
The more information you give up front, the faster your issue can be resolved.
A DxDiag is a utility designed to display the specifications of your computer hardware, as well as to test DirectX software, including sound and video. If you are asked for this information, it helps the support group relate your gaming issue to your personal computer.
To create a dxdiag.txt just go to Start -> Run (or Search in Vista) and enter dxdiag and click OK. Once the program has run its course, click "Save all Information" and it will output a txt file that you can attach to your email.