Once again, does Event Viewer show any errors that might help. If you do not know how to start Event Viewer, type eventvwr.msc in the Start Menu search box.
You might also open the Device Manager. If you select view, resources by type, you can see a list of the items that might be using it. I do not really know of a way to tie the information together, but maybe it will give you an idea of what might be causing the high interrupt traffic. The Network adapter is probably on the list.
Does you mouse ever lock up when moving?