What do you mean by outgoing issue? The firewall can very well stop outgoing traffic if that is what you mean.
Anyway, All virii are not stopped by the firewall, no matter how many firewalls you have. If you can surf the web, then there is incoming traffic, then virii can reach your computer. You should have an anti virus to check your computer from time to time.
Anyway, your VM won't stop attacks from abusing flaws in Windows XP network stack, because the traffic must pass through Windows's network stack before it reaches the VM and go through it again to get out of the VM. If you have a good soft firewall, it will be exactly the same as a VM because the VM is a software! The only difference is that the VM will run a pleatora of useless stuff in addition to the firewall.
If you fear spywares, virii and registry breaks, you should not run Windows at all. I believe virus scanning and reinstalling from time to time is part of the Windows experience...
Last edited by Agrouf; 06-16-2009 at 03:57 AM.