Is router firewall good enough ?

i am using wired edimax router (br6104k) and i enabled the firewall feature in it with all the options.
Do you think that this built in firewall is enough to protect the computer from "outside" problems ?
i also use AVG free antivirus and MS SPYWARE.
I had no problem till now, but 2 of my clients which did not have a router and a firewall had a nasty trojan that they got rid off only after installing NIS 2005.

Most routers have a firewall that is more than enough to defeat most external intrusion attempts. Unfortunately, they can't stop viruses, spyware & Trojan Horse programs. You need a mix of adware removers, antivirus programs, and good common sense policies (Group Policy Objects on a server based network) to be secure. The biggest problem is educating users about the malware component of most "free" screen savers, and so on.

If you have a workstation connected to a Windows 2000/2003 server, the station needs a users profile set up as a Power User or higher for many programs (such as Citrix) to run, and that can give them the ability to download all kinds of junk. My advice is to beat them over the head with security. If your client has a peer-to-peer LAN, sell them a server and get the system centrally managed.

Thank you.
The clients problem was solved after installing NIS 2005.
I will think about the advice of managing network via dedicated server.
Have a great weekend