I am in the UK we just got this game here but first I am wondering if there a difference in the US / UK version of the game (for the PC)?

Next to none for the most part... except the UK version comes with FFXI, Rise of the Zilart, and Chain of Promathia. The US has to be buy Promathia separately.

Also, the in-game help is available in either English, French and German. That, and the box art is different (it just has the game's logo on the front cover), with a front cover which opens revealing Yoshitaka Amano's artwork for the Chains of Promathia expansion (the US PC version has part of the Vana-diel World Map as well as the logo) .

Nothing much else is different as far as I can tell, although there are 7 discs included compared to the 5 discs for the US version, due to the CoP expansion being bundled in with i the European version.