Just for safety's sake when you have publicly available services you should DMZ them though I don't recommend the D-Link's DMZ "solution". You could but a second D-Link and place it between the LAN and the public machines or use the box you mentioned to create a DMZ. Either way would work just fine....

Cheyenne: I can't afford AV for all my boxes and I can "enforce" is since I have other companies inside my network..... But my firewall does a great job of stripping all executables from SMTP incoming streams and stopping the (l)users from getting to their personal email.... Even on those machines that we have set up for the public to use....