Your 2wire router should support NAT ( Network Address Translation) feature and you should get one static (global) IP address for each server behind the router in your LAN.
With NATing you can map local IP addresses to global (static) ones , then your servers will accessible from out side world.
but I suggest, like other fellows did, using a decent firewall with or without DMZ for your case.
You can go for ZyWALL2 plus or ZyWALL 5 UTM firewalls to get the job done in professional way!
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