Canada - like America - is R1 for DVD and NTSC for video, the UK is R2 and PAL, so they won't officially work. That said, many newer (even budget) players in the UK these days are multi-region/NTSC compatible - though they may not advertise the fact - or (in the case of DVD players) can be easily made multi-region by pressing a few buttons. I would imagine that it isn't that hard to source equipment capable of playing UK discs and tapes in Canada.