I think I may have found the problem, I only installed BF2 and FH2 the other day (been off it for quite a while and a recent new pc build) and the 1.5 patch perhaps didn't register? I did install it but looking at server lists in BF2 just now they appear as 1.41.
Removed FH2, installed 1.5 patch and installing FH2 again.
I expect there is a settings file somewhere in my documents (moved it around through a few different builds) that is saying 1680x1050 res for FH2 which it can't do pre BF2 1.5.
Anyways I'l let you know if its works