There was a Parallels update available which I installed and it didn't help. In fact, it got more interesting. The wuaucIt.exe file invited some friends over for eggnog, since lots of other stuff was crashing; like SharedInt.exe and more importantly, Explorer.exe. Every few minutes I was rewarded with messages saying that Explorer.exe had failed and Windows checked for the potential problem, which it never found. The Kaspersky Anti-Virus tool, which came with Parallels, showed up each time I rebooted. It gathered information to send to its server but when it tried to send the packet, it got nowhere and sent nothing.
Eventually I decided to trash the installation and start from scratch. This time I told Parallels to use all 8 processors, which according to iStat is a good idea, since the load is well balanced between all the processors. When it ran, it seemed to run much quicker. But it didn't solve the problem. This, I thought, was odd since I've been running both XP and Windows 7 on my MacBook Pro via Parallels without a burp.
After a good deal of searching, I found the solution on the Parallels forum in a thread that started before Thanksgiving. There is a problem with Kaspersky Anti-Virus-Protection and Parallels Desktop 5.0 on some machines. The answer is to uninstall Kapersky and install something like AVG 9.0 (which is free).
I wasn't convinced that it solved the problem totally, so I ran my iTunes library along with playing movies all night to put the installation under some stress. When I came back the next morning all was well.
On December 11th, in the forum thread, a rep from Parallels copped to the problem: they were working on it, he said, and asked everyone who was affected to send in a bug report.
It's not clear which Macs are affected, but the thread only mentions it happening to a quad core Nehalem Mac Pro with most respondents not reporting what Mac they owned. Well, the iMac i7, at least, is affected as well. The only commonality I can see offhand is that iMac i7 and the Nehalem Mac Pro are both quad core. Whatever machine you have (except the Macbook Pro, where both someone in the thread and I can tell you that there is no problem), at the first sign of distress, jettison Kaspersky and your holiday season will be much brighter.
If you've seen this, please tell us in the comments. It would be quite nice if we can figure out which models are prone to this hell, and which aren't.
And that's the first post written on my new iMac.