OT: Question regarding hardware or software firewalls...

[EVO VIII Chris]

I am debating on the purchase or a hardware or software firewall here and I am looking for some opinions and help. I know that I could either go with a hardware firewall or software firewall. I run my own server and there are 3 computers that recieve IP address from my server and my server is also the DNS server for the other computers as well. It is also the print server and so on. Currently I am just using a 3com network card to assign the other computers IP address and I am also using Black Ice for a software Firewall. I only have one IP address from my ISP so I have to have the network card to issue the other computers IP's. Anyways I am wondering if hardware or software files are better in any way? Do either or them have advantages or disadvantages I should be aware of? Would it be possible to run both hardware and software firewalls? I am just looking for opinions on which route to go and what is a very good software firewall for small buisness networks and also a good hardware firewall.

Thanks guys
Chris