
That's not a particularly huge budget when it comes to surround sound, and so your choices will be limited. If you want an "all in one" type system where you have a head unit consisting on a DVD player and surround sound processor and all 6 speakers (Front L&R, Rear L&R, Centre, and subwoofer) then consider either the DCS-363 (approx £270) or the DCS-370 (approx £350) both from Pioneer.
However, I think you should seriously consider going down the separates route instead, and buy something like the Kef KHT1005 (approx £280) and combine this with something like the Denon AVR-1507 AV Receiver (approx £225). Going down the separates route will give you the best performance and flexibility to upgrade in the future, although it will mean a larger outlay.
Good Luck.