Jammer

I have several HD VOB/TS files I have recorded on a DVR. I have changed the extension to MPG. I was told that was ok and made them easier to edit. I would like to cerate a DVD of the shows I want to keep. When I try to edit using IMGBurn and playback the edited versions the video is out of sink with the video. I have searched this form and did not find an answer as to what I am doing wrong any ideas?