The Wishlist feature in Magento is enabled by default but is rarely used. Quite often Magento users experience problems with this functionality when they install a new Magento theme. The easiest solution in such cases is to disable the Magento Wishlist feature.
To do so, log in to your Magento admin panel and go to System > Configuration. In the menu on the left find the Customers section and click Wishlist. Then click General Options and set the Enabled option to No. Click Save Config to save the change.
Now that you have disabled the Wishlist feature, it is a good idea to disable the output of its module Mage_Wishlist as well. You can do this from System > Configuration > Advanced section > Advanced. Click Disable Modules Output and at the bottom of the page find Mage_Wishlist. Set it to Disable and click Save Config to save the change.
Now you can flush the Magento cache and visit your store's frontend to verify that the My Wishlist option is no longer displayed.