I've just tried the same procedure the only difference being I am running Vista Ultimate. Oh and my CPU usage is about 6% with normal processes running (about 20)
- view cr2 file in bridge (no problem)
- open in ACR (no problem)
- process and save as tif (no problem)
- opens in CS2 (no problem)
This is not a solution Fi, just confirms that it should work. I can only add that it might be memory or is your Swap Disk too small, full etc.