I've been using the Nod32 security suite for some time now, and out of all the others that I've tried, it's great (low memory footprint, fast, fairly cheap). However, I've been installing a lot of software lately, and the thing that's been annoying me is having to allow each program access to the internet. Yes, I know it's a one-time thing, but I would rather not even have to do it in the first place. (It's also a pain when I have to reformat/reinstall.) Thus, I am considering removing the firewall entirely, and just sticking to the antivirus.1
So my question is: Is not having a firewall unsafe, even with an antivirus? Obviously I'll never be 100% safe (not even an antivirus can completely protect me, and I realize that), but I don't do stupid things, I back up my data, etc. Does not having a firewall open up any dangerous vulnerabilities that an antivirus cannot cover? If I somehow get some malware on my hard drive, will not having a firewall keep me from being able to remove it? Or will it, for the most part, not make a difference? And if I do need a firewall, is the one that comes with Windows sufficient?
Note that I'm not really interested in those 0.1% corner cases, I'm talking about the general majority of malware, and what implications not having a firewall may pose for me. Oh, and I'm using Windows, obviously. :)
1. I am definitely going to keep the antivirus just in case, mostly as a last resort. Please don't tell me that I don't need one.