Well I connected a server few minutes ago and host (booty guy joe)'s connection was cable but I couldn't move a second, abuser was there too and they could move! My connection is 56k but it mustn't be too slow! Please help!

It is probably not due to your modem (56k) but maybe because the second host is too far from you, or because he have bad connection himself. If you want to know the ping of a server before joining, you can use my modified engine with ping displayed in multiplayer join menu (link to download on the main COOP or DIE page).

Yeah, thanks for the info Pat.