I have a server and a box that cannot communicate, a server(fedora 12) with two nics on it, directly connected to say 192.168.1.0 and 192.168.2.0 the route table looks like this
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.1.0 192.168.1.1 255.255.255.0 UG 0 0 0 eth0
192.168.2.0 * 255.255.255.0 U 0 0 0 eth1
eth0 = 192.168.1.15
eth1 = 192.168.2.1
and a directly connected user (Mythdora) on the 192.168.2.0 network with ip 192.168.2.2 and route table like so
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.2.0 * 255.255.255.0 U 0 0 0 eth0
the cable is a crossover and it works all three nics work
Try not to state your actual problem at the very end prefaced with "as a note", but I think I get what's going on here after reading through a few times.
Clearly you have two machines you want to connect on 192.168.2.0/24. One of them is intended to act as a router to the 192.168.1.0/24 network.
First, I don't think this is necessarily the cause of your problem, but it doesn't make sense for your server, directly connected to the 192.168.1.0/24 subnet as 192.168.1.15, to have a route for the 192.168.1.0/24 subnet which is another machine on that subnet. Maybe explain what you were trying to accomplish here.
Your laptop test may be flawed, or you may simply have explained it confusingly. You should only be able to ping the server using a 192.168.2 address when connected to the NIC which is configured for that network.
I don't mean to be overly critical of how your question was asked, but I often find that when I am flustered with a situation and it doesn't make sense, explaining it in a way that I feel others should understand helps me to find the answer myself. :)
so i solved it, i narrowed down and deleted all the routing except between the box and mythdora and still nothing, I then gave up and installed mythbuntu. worked without editing iptables