Replying to .mts and .cpi files

hey I just got a Canon Vixia HF R10 and when I try and get the videos off it has them in .mts and .cpi formats.

When I try and play the .mts videos in Windows Media Player it is all skippy, the sound is fucked, it has a watermark in the corner and the video goes longer than it says it does.

Does anyone know anyway I can get these into an editing program (I have Windows Movie Maker but I can get one) or convert it without it degrading the quality and shit

thanks