Yes, you can do it in Linuxconf. It is under Networking > Client Tasks > Routing and gateways. You'll want to set the default route to the eth0 card, and set a route to your local (192.168.1.x) network. Linuxconf might get confused, though.

You have two default routes at the moment, and that just doesn't work

You can remove the default route to 192.168.1.1 by doing:

route del default 192.168.1.1 eth1

Then add the route, with gateway, to your local network, through eth1:

route add -net 192.168.1.0 netmask 255.255.255.0 gw 192.168.1.1 eth1

All should be well after that.