Did you try these options that were mentioned in that link?
OPTION ONE:
Through a Download
1. To Remove the Search Context Menu Item -
A) Click on the download button below to download the Remove_ContextMenu_Search.reg file.
B) Go to step 3.
2. To Restore the Search Context Menu Item -
A) Click on the download button below to download the Restore_ContextMenu_Search.reg file.
OPTION TWO:
The Manual Way
7. To Restore the Search Context Menu Item -
A) In the right pane, right click on LegacyDisable and click Delete. (See screenshots below steps 4, 5, or 6)
B) Click Yes to confirm deletion.
C) The registry will now look like similar to this. (See screenshot below)
NOTE: This example is from step 4. Just substitute either step 4, 5, or 6 for the one you selected instead.
D) Go to step 9.
You have to be on the linked site for those quoted instructions to make any sense.
How to Restore the Search Context Menu Item after Installing the Vista SP1