bitdefender/norton etc

I have an Asus F3 series laptop with more resources than I know what to do with, get a 4.8 score with Vista and almost never go above 35 percent CPU until last week......

I used to use Norton years ago until I discovered Pctools products and then Bitdefender which I've used for about two years now with not a single problem until last week when my 2008 subscription expired and I renewed and that renewal makes me download internet security 2009 and well guess what? It won't install/run on vista home or ultimate, just totally locks the system and the only way out is a hard shut down, start up in safemode and do a system restore.

Turns out others have posted same in the bitdefender forum so it looks like it might be a big "ooops!" On the part of bitdefender and there is no fix yet.

Unless someone here happens to know?

Secondly, needing a security system I decided to give Norton 360 a try and what a mistake that was, as soon as I touch the keyboard is doesn't take much to max out the CPU to 100 percent and bog down my system.

when Norton did the registry thing is off'd a couple of needed entries and .dll's, nothing critical just anoying.

My quickbooks 2007 no longer works so I'll have to re-install that, guess it had a disagreement with Norton during the install and quickbooks lost

Norton doesn't seem to have improved in the resource hog department over the years.

So I guess my question to the experts here is does anyone know how to get Bitdefender internet security 2009 running in vista? I bought the key, would love to stay with that system and it doesn't use hardly any resources and just works with not one single problem in the two years I've been with them, it's just won't go in vista.

Thanks.
I'm a news camera operator in Toronto/ontario and cover the GTR regionals but with the 14+ hour days I'm not on here that often as you can tell.

You're thoughts? Obviously remove Norton, if I can't run bitdefender yet...would windows firewall and defender do for now?

Thanks again,
Mark

Asus F3 series
Vista ultimate
Sp1 and all updates
4GB RAM
Intel 2.G processor
160G HD