The files produced by your DVR are interlaced.
You can get a much better quality video by de-interlacing.
I'm on a Mac and use the 'MPEG streamclip' (freeware available from the Apple site), I'm sure that there is plenty of equivalent stuff for Windows too.
If using MPEG streamclip - open the and then 'convert to MPEG4'.
Choose the following options:
"Frame Blending" (not essential)
"Deinterlace Video"