Performance issue with Vista on a fast computer

I'm new to vista, I installed vista with SP1 on my new computer :

Q6600 with 4 gig ram DDR2
Gforce 7800GT

I run a battery of test and benchmark on vista and my system is performing as it should.

my cpu usage is around 5-10% most of the time

There's just a problem with the mouse and keyboard, when I move my cursor it seem to freeze for a few ms frequently, same thing when I move a window. Sometime when I type the key appear a bit after I typed them.

But everything else work fine. Any idea what could be the problem?

This is kind of a general symptom with many possible causes I think. I would start with either task manager or it's big brother, process explorer http://technet.microsoft.com/en-us [...] 96653.aspx and try to determine if any background process is spiking ram or processor usage at those times when the system hangs.

You might want to look over everything you have installed since the time when the system was running without this problem.

I'd also scan for malware and update all my drivers, particularly sound and video. And if all fails try rolling system back with system restore.

You might also try running the system in safe mode to see if same thing happens there.

Has this same configuration ever run properly or did it hang like this from the start?

If Kapersky is giving troubles, you may want to try NOD: http://www.eset.com I went for the whole suite, and it has run flawlessly on Vista 64 with VERY minimal performance impact.

Any evidence of this or is that just a guess?

Yea. Take a look at NOD32. Great Antivirus and Very light on Resources