[CentOS] Advice sought: Virtual Win7 on Centos 6.2

Folks

I have a new laptop running Centos 6.2 64-bit.  I'd like to put a 
virtual machine running Windows 7 (licensed), with full audio/video 
functions, and good response.  Which virtual system would you 
recommend?  I can think of KVM, or VirtualBox, or ...?

The "good response" requirement pretty much excludes a web-style 
video presentation.

Opinions solicited.

David Kurn