Staric 0 Newbie Poster

What I have is a linksys wrt54gs(dd-wrt) router assigning private ip's to my workstations. I also have a Windows Server which i need accessible for Windows Remote Desktop Connection to my remote office in Costa Rica. I'd like to have the server have one of my 5 static public ip's(so i can use a host on one of my domains) but the only way i was able to set this up properly was by putting the server on the modem directly not behind the router. When i tried using NAT, it would assign the public static ip but Windows would say i still cant connect to the internet?. Im wondering if having my server behind a NETGEAR ProSafe VPN Firewall would be enough? Before i was getting thousands of login attempts each night on my server