How can I avoid the video lag when I convert videos into a new format?

I'm using Tipard Video Converter to convert .mp4 videos from my camcorder to .mpg so I can edit them in another program. The conversion process always results in a video lag (compared to audio) by the end of the video. It's like the video gets slower and slower. I have some options to change the converted video's resolution, frame rate, and video bitrate. I can also adjust the audio's sample rate and audio bitrate. What can I do to avoid the lag?How can I avoid the video lag when I convert videos into a new format?
All of the outcome of your newly made video is the result of your hardware. If you have bad hardware, then your outcome is going to suck. If you have great hardware, you will be surprised with your outcome.