Nope UK and USA are contry specific, Japan is region 2 The USA one has the naff screen (with more reports of dead pixels) The Jap ones (as usual) are better since the Japanese market is harshes, the UK ones will use the same screen but will be rejion bound. Version 1.00 and 1.50 are all able to play hacked games, version 1.51 &1.52 disable hacked games and homebrew. Version 2.00 also does this but adds a browser for wlan browsing. My advise is to go with a Jap one then eBaY it for the games which will be cheaper than the ones sold in the UK.
Also if you get a prog called "TooPSP" and a prog like dvd shrink etc, you can add a movie dir on the memory car (500mb min for a full film in mpg4 formatt) and watch it, rather than shelling out the same movie on UMD. 1 gig recomended.