I think I know what is wrong. Common problem I used to see with old people and computers when I worked tech support.
Right click your desktop, click properties in the menu. That should bring up the 'Display Properties' dialog. Click on the 'Settings' tab, and then click the 'Advanced' button towards the bottom of that section. That should bring up the monitor and graphics card properties dialog. Under the 'General' tab, in the 'Display' section, look and see what DPI you are set to. I am betting that you are set to something above 96, probably around 120. If you set it back down to 'Normal (96 DPI), it should correct your problem.
If that doesn't help, I don't really care. I do not work in tech support anymore.
Good luck.
-Zach