The indexer isn't supposed to bother you while you are using the computer.
Although it technically is using your disk all the time, it notices when you
are trying to do something and lets the stuff you are trying to do go first
(in the same way that Automatic Updates can download in the background
without affecting your internet browsing).
It should finish its indexing within a day or two, depending on how much
stuff you have on your computer. The benefits of having the index are really
worth waiting for, IMHO.
However, you can disable the search indexer this way:
-Click Control Panel
-Click System and Maintenance
-Click Administrative Tools
-If asked for permission, click Continue
-Scroll through the list and find "Windows Search"
-Right-click it, and click Properties
-Click the dropdown box next to Startup Type
Microsoft MVP - Windows Shell/User
Windows Vista Support Faq