wucrtupd.exe is a critical windows update, basically its like the little globe that updates your windows, but it has some problems and complications.
What it tries is to periodically contact ms and see if you need any updates, and if it does right and connects right then it will tell you that you need to upgrade. Some people have suggested renaming the file to something like Sucrtupd.exe, i am not sure how much that will help. You might want to see if you can find somewhere to turn off auto updates, or try updating your windows installation. I have heard that norton sometimes causes this problem when it tries ot come up.
Sorry can't tell you more but just really learned the basics on it myself.
