If you have a dvr I'm guessing the dvd/vcr is just for watching old stuff you own, not recording. All you'd have to do is connect it directly into your tv's red/green/blue video-red/white audio inputs (Component). Probably Component 1. Then choose that input from your tv's remote when you want to watch it.
Be sure to configure the dvd/vcr in it's own set up menu for 16:9 aspect ratio. There may be other color, etc., settings you have to adjust for an HD tv, check it's owner's manual.