No connectivity

I just changed my server from Winxp to a red hat 9. The external connection (internet) is perfect as I can ping my IP but the other systems cannot surf the net through the Linux. I am confused..........
What do I do:confused: Yes I am quite new to Linux Red Hat 9.2 Pls can any one tell me how to go about it rite from the installation stage... Please

have you by any chance enebled routing, Nat and checked the firewall

xavistyles, I am having saem issues did you ever find a solution? Please let me know...Thanks.