Most American and Canadian DVD players are not compatible with foreign DVDS. The US and Canada is in Region 1 (and we use the NTSC system.) The United Kingdom and Western Europe are Region 2 (and use PAL.) The systems are not compatible.
I own a Phillips DVD Player/Recorder that is all-region, code-free, and converts PAL to NTSC.
Amazon has a nice selection of DVD players for several for sale. Definitely worth the investment if you want to watch British and foreign DVDs at home. But do your research first. You won't find these players in big box stores, including Best Buy.