Was the time zones listed earlier and when was the last time you were able to change time zones?
Run System File Checker (SFC) scan and check if that helps.
The sfc /scannow command scans all protected system files and replaces incorrect versions with correct Microsoft versions.
1.Click
Start, and then type cmd in the Start Search box.
2.In the results area, right-click
cmd.exe, and then click Run as administrator. You will be prompted to type the password for an administrator account. Click
Continue if you are the administrator or type the administrator password. Then, click
Continue.
3.At the command prompt, type Sfc /scannow, and then press ENTER.
The scan may take some time, so be patient. Windows will repair any corrupted or missing files that it finds. If information
from the installation CD is needed to repair the problem, you may be prompted to insert your Windows 7 CD.
