Hi Debbie,
Welcome to Microsoft Community.
Based on the description, it appears that you are having issues with mouse. I will surely help you with this issue.
1) Have you made any changes on the computer prior to this issue?
2) What is the make and model of the mouse?
Method 1: I would suggest you to follow the steps to boot the computer in Safe Mode and check if the issue persists.
http://windows.microsoft.com/en-US/windows7/Start-your-computer-in-safe-mode
Method 2: I would also suggest you to follow the steps from the link and check if it helps.
Troubleshoot response failures in wireless keyboard or mouse
http://support.microsoft.com/kb/838398
I hope it helps. If you have any issues regarding Windows in future please let us know. We will be happy to help you.