Heres the facts on importing games on all the consoles :
The solution for Gamecubes is substantialy easier, you just buy the "freeloader" boot disk. This costs around £13 and is easily obtainable at your local video game shops, or play.com /
amazon.com. There could be an issue with video modes on some games however, as US cubes use S-Video and do not have the RGB mode that UK consoles have. I was never able to get UK Pikmin working on my US Cube.
The PS2 requires, as folk have said, a mod chip to be fitted. There is a boot disk solution for DVD's, but not for games. There are several different chips available, but the fitting is quite tricky for anyone inexperienced.
XBOX is the same as the PS2 for Games in that it requires a mod chip to be fitted. Fitting is somewhat easier as all solder points are on the top of the board (for the popular LPC chips), meaning it doesnt have to be removed from the case. Expect to pay a fitter around £40 for supply and fitting (well thats what I charge anyway). The solution for DVD playback is different to the PS2 though, the Xbox requires an external dvd dongle to be fitted, which doubles as a remote control receiver. The xbox will lock onto the first dongle thats used on it, so if you want region 1 dvd's, buy your dvd playback kit from a us stockist. You will lock out region 2 dvd's forever if you do this though (unless you get it chipped).
For older consoles :
Dreamcast - a freely available boot disk (called Utopia) is available for download on the net (
www.gamecopyworld.com). this can be burnt with Nero or other CD writing software. Its simply a matter of booting to Utopia then swapping disks.
PS-One - Modchip is the best solution, expect a fee of around £10 to have one fitted. Alternativley, there is a boot disk available, though hard to find, or for really old models, there is a disk swap method.