appearance and theme in control panel

Click on the link for information on how to remove the Appearance and Theme tabs from the Display properties... it should guide you to the registry settings that have removed the tabs, and just do the opposite by deleting the DWORD values named as "NoDispAppearancePage" and "NoDispThemePage" or by editing their data from 1 to 0. If the change doesn't take effect immediately, restart the computer and check again. After that, do a virus and a malware scan to remove possible infections that may have changed settings.

http://www.liutilities.com/products/registrybooster/tweaklibrary/tweaks/10911/

EDIT:
This solution is much easier to do... download the script named "showalldisplaytabs-xp.vbs" and execute it.. that should restore your display tabs.
http://www.winhelponline.com/articles/38/1/Restore-missing-tabs-to-the-Display-properties-dialog.html