Forget checking it. Just turn it off and back on. Some are dismayed that Microsoft left a bug in this one where this screen tells you it's in DMA mode, but isn't.
Besides the Worms, be sure there are no other pests. The usual tools are Spybot, Adaware, Cwshredder and Housecall.
My one year old turned off my computer without shutting it down properly over the weekend. Now it seems very sluggish and takes a very long time to do anything, especially with the internet. All virus scans have shown no Sasser worm and I have turned System Restore on and off and rebooted dozens of times.
Any ideas on a solution? It has been turned off before that way and I have never had such a problem.