Avast 5.0.454 Firewall

I am running Windows 7 X64 and Security Center indicates Avast & Windows Firewall both active and may cause conflicts. Please see attached clip. Should they both be on?

Indeed, it’s advisable to run 3rd party firewalls with Windows one also. At least, AIS and Windows one work together very nice.
Anyway, you could disable manually the Windows one if you want.