Hiya tikifrei
Could you send links to the details of the TV's you've seen which have Multi system capabilities please? I've so far not seen any, not saying they don't exist, but there's really very very low demand for them in the mainstream.
Persephone - a multi system TV or Video product is one that has the IC's inside that can handle the various television 'systems' that exist in different territories of the world. The USA uses the 'NTSC' system to (basically) generate the video picture you can see. The UK uses the 'PAL' system. Products that are one or the the other, are not compatible with diffrent video systems (a UK PAL tv cannot display an NTSC signal and vice versa)
The multi region DVD players you can buy for relatively cheap, can provide a solution, they'll 'playback' a US NTSC DVD and be able to 'display' it on a UK PAL TV. In that respect you'll be able to move forward.
If you look through the gaming posts, you can bring over your US XBOX, I'm not a gamer, but some of the members here are and can give you the low down on how you can (or maybe cant!) use a US Xbox here.
Alternatives could be that you can 'rip' your USA Film DVD's to computer files and playback from your computer to your tv, not sure if the same type of thing would work with games though.
Lastly, shipping over a large flat screen TV is possible, but the insurance quote will go up quite a bit once you mention you have one in the container. I 'Think' all big screen TV's like this need to be transported vertically, if they go horizontally, it's possible with the vibration the middle of the screen can flex can break. It's generally not a good idea to ship large screen TV's like this.
Hope this helps
Cheers, DtM! West London & Slough UK!