yanksfan,

How old is your linux kernel? I'd suggest IPTABLES over IPCHAINS because, IMHO, it's designed better and has more flexibility to meet the needs of a website without compromising security (there are a few security flaws in IPCHAINS in the general design of it).

IPCHAINS can use kernels 2.1.x and higher.

IPTABLES can use kernels 2.4.x and higher.