#1 - Jan. 6, 2010, 9:08 p.m.
Pir,
With the game closed please try moving or deleting your WTF, CACHE, and INTERFACE folders out of your World of Warcraft directory. These are temporary cache files that will be recreated by the game the next time you launch. Moving them to the desktop makes it easy to replace them if necessary.
Please also note these folders contain your video/sound settings and UI addons. By moving or deleting these folders you will also remove any saved preferences, or UI addons you may have added. However, in order for us to troubleshoot the issue we need to remove any modifications to the game and make sure we are diagnosing the default settings.
NOTE: Please also make sure to remove any and all addon auto-installers or auto-updaters you may have, as those can automatically reinstall addons for you, possibly causing further issues.