Thanks Craig,
I never thought of that I will give that a try now. I think your solution would definately solve my second problem but I am not sure how I would go about solving the first issue.
Basically when an admin logins in they will be taken to the admin homepage. On the homepage there will be a image link. I would like a little red alert image to display beside this everytime a new user registers. So if five user registers since the last time the admin clicked the image link the little red alert image will display "5". If admin clicks the image the alert disapears.