It may be called autocomplete/suggest rather than instant - I'm not sure.
I really dislike having all those suggestions come up while I type in the google search box.
Here's an easy way to turn them off.
Compliments to bluequoll on 7/30/11 on the google product forum
Paste http://www.google.com/webhp?complete=0 into the google address bar and hit enter.
The URL will expand. You can test it now if you like.
Copy the new URL onto the clipboard.
Open favorites and right click on google.
Click properties and on the web document tab, paste the new URL into the URL box and click ok.
If google is your home page, you can paste the new URL into Internet Options - General - Home Page and click ok.
I hope this helps someone.
Edited by Eles, 20 August 2015 - 12:05 AM.