A few pointers.

> I spent all day reading about gateways, routing, etc. in order to
> setup
> Linux as my gateway.  I actually got it setup, but from what I
> understand
> the approach I tried is terribly insecure.
> 
> I did this and got it running:
> # echo 1 >/proc/sys/net/ipv4/ip_forward
> # ipchains -F
> # ipchains -P forward ACCEPT
> 
This is a security problem.  Default policy should always be deny unless
there's a real good reason.
ipchains -P forward DENY

> # ipchains -A forward -s 192.168.1.0/24 -d 0/0 -j MASQ
> 
That's fine.

> That works, but everything is reset when I restart my network.  And,
> as I
> read, this is apparently insecure.
> 
Reset?  What do you mean?