Gateway/Firewall setup

[Una]

I have been given the task of setting up a firewall/gateway box for small business, and I was wondering if this setup sounds like the best topology.
For being on a budget I am either going to use smoothwall or OpenBSD as the firewall/gateway box.

Should look something like this,

Internet > ADSL router > Firewall box > Switch > Internal Network.

I need to setup VPN access so that the employees can work from home (I.e so they can use remote desktop). Is this pretty simple to setup port forwarding with smoothwall or should I go about this another way?

Thanks.

 

[Una]

Yeah they will be windows only, so thats not a problem. I know a integrated firewall/adsl router would be the best solution straight to the switch. However I have a 1U rackmounted server I want rid of that will be ideal for the a firewall box hehe. Thanks for the input guys.