I instaled NetTurbo the last day and now my Ie crashes from time to time, I can't load Windows Update or MSN Messanger "My Inbox", can't sometimes open new links.
I have scaned the computer with Spybot S&D 1.2,Ad-Aware 6 build 181, Norton Antivirus Pro. 2004 and I did not find anything. My computer has slowen down and D/L speed has gone down too. Can anyone help me ?

Your safest bet is to uninstall NetTurbo.
Contrary to popular belief, none of these so-called accellerators do anything other than make their sellers richer. Your PC does not gain an ounce of speed.
The only utility that does anything usefull, is DrTCP and is FREEly available here:
http://www.dslreports.com/drtcp

I've aldready uninstalled NetTurbo and Ie still crashes and now the comp. loads few svhost.exe and one of them takes alot of memory sometimes.

You may have been infected by a virus.
Download Adaware (Build 6.181) and Spybot S&D (V1.2).
As soon as you start each of these programs, run the Update-function first, before you start the scan.

I've already scanned the computer with Spybot S&D 1.2, Ad-aware (Build 6.181),Norton Antivirus Pro. 2004 and nothing found anything.

Did you mean svchost, or was svhost the correct name. If it was svhost, I found a few references to a virus called "w32.Randex.gen". as detected by NAV. svchost is a generic windows process and can be associated with hundreds of different things, both legit and suspicious. It is not uncommon to find multiple scvhost.exe processes running at any given time depending on what apps are running.

Have you tried repairing IE?

I've just changed to Mozilla and everything seams ok. But Windows Search does not work now. :/