The game can be started with a few parameters, I'd recommend the following to you:
-a --noanimback Don't use animated backgrounds
-f --nofade No fade effects
--nograss Don't draw the grass
So you'd start the game like this: dom3 -af --nograss
As for hosting games, there are stickies in the Dom3 MP forums regarding that. Quite a few people offer to host games, including Gandalf, llamabeast (for PBEM), myself and others.