f12 key problem

Running xp pro sp2. Lately, my F12 key produces an expanding red circle which is centered where ever my cursor is located. If I assign an operation to this key, it performs as it should, but not until the red circle finishes its repetitions. This can be up to about 7 seconds, and is quite annoying. It seems to some sort of cursor locator. Anybody know how to get rid of it? Thanks