I had a problem with vsmon.exe. Taskmanager showed me an increasing of "E/A (read)" amount.
Search on Google for
"vsmon hdd last"
"vsmon hangs system"
or other Keywords didn't give an helpful answer.
Here is my hint:
That problem is caused by some applications, if you block them in your Firewall settings. In my case it was the Intel "Local Manageability Service". Allow the connection to internet and everything works fine. Other solution: Uninstall the Service
By the way:
My System is a Lenovo T400, 2,53Ghz Core2Duo, 2GB RAM
WinXP Professional Sp3
ZoneAlarm Version: 7.0.483.000
Sorry for my broken english