Not responding on DVD menu selection

[zyonuf79]

TV-Server Version:
MediaPortal Version: 1.0 rc2 SVN-Snapshot:-08-09-2008 09-21h - Revision:20268
MediaPortal Skin: Blue Two Wide
Windows Version: Vista Business x64 SP1
CPU Type: AMD 2.4 GHz
HDD:
Memory: 2 GB DDR2 800
Motherboard: Biostar TF8200 A2+
Video Card:
Video Card Driver:
Sound Card:
Sound Card AC3:
Sound Card Driver:
1. TV Card:
1. TV Card Type:
1. TV Card Driver:
2. TV Card:
2. TV Card Type:
2. TV Card Driver:
3. TV Card:
3. TV Card Type:
3. TV Card Driver:
4. TV Card:
4. TV Card Type:
4. TV Card Driver:
MPEG2 Video Codec:
MPEG2 Audio Codec:
h.264 Video Codec:
Satelite/CableTV Provider:
HTPC Case:
Cooling:
Power Supply:
Remote:
TV:
TV - HTPC Connection:

This happens on DVDs that are stored on the hard drive. I am only able to select two menu options and then M.P. freezes on my next attempt at a menu choice. I have to force it to closed with the task manager.