Hi,
Too many extensions slow down the browser... I have Mozilla Firefox with Google Toolbar ... and use Flashblock.
Flashblock blocks flash, and it is very cool, you still can watch flash just by clicking on an F Button.
Nandu: Html composer, is great... and I created a complete site using Nandu.
NoScript: Blocks scripts if you are having script programs.
(no longer use this but it is good)
Karl