Hard to generate many ideas since you didn't provide any info wrt system or configuration. However, it "sounds" like a video adapter issue, make sure latest video drivers are installed, try turning off hardware acceleration, etc.
My appologies, I am using xp Pro, service pack 3, 4gb RAM,Nvidia Quadro FX 1700 graphics card.
Strangely I also get out of memory messages after processing a number of files. I then have to close the PC down and start up again.
First thing to try is to up your disk cache size in Camera Raw preferences, assuming you have space on your hard drive. It's probably overkill, but I have mine at 20gb. The default value is often too small to process many images at one time.
I already have my Camera Raw cache set at 20gb. I still get out of memory messages!
Ok, some other things to look at/try:
1. Purge all of your caches via Photoshop/Bridge/ACR preferences.
2. Allocate about 70% of your total ram to Photoshop in its preferences.
3. Don't want to be insulting, but make sure you have plenty of space left on your hard drive.
4. Make sure all updates are applied to Windows XP and to Photoshop.
5. Use task manager to see what else is running when you use Photoshop.
6. Turn off any virus checker to check for interaction.
Added by edit - Might be helpful if you posted a screenshot of the error msg.
Hate to say it, but it might be time to consider getting a new 64 bit computer with a modern OS.