I have Ableton and Cubase 5 both running fine on Windows 7 32 bit. I can't tell you how 64 bit will work. From what I have read Lexicon does not have 64 bit drivers for the Omega so drivers could get dicey. That HP Laptop only has 4 gigs of memory anyway so you may want to think about upgrading to Windows 7 32 bit and not 64 bit. No matter what, ditch that Vista junk.

Don't worry about firewire unless you need an interface to record multiple simultaneous inputs. USB is fine for most home recording.