Firewall Software Needed??

[badadjective]

Is it necessary or even recommended to have a software firewall on a PC connected to a router? All of the firewall settings on my router are enabled, is that secure enough for a home PC? I just hate all the nag screens of software firewalls asking permissions for programs to connect and so forth.
Any insight is appreciated.

 

[IronDuke]

Not really necessary with a router if it using NAT. Still I think it is wise to have one. I use Zone Alarm and Sygate (not both on one machine). There should not be that many nags after it is set up. Better the nags than the possible consequences.