Most of those combo units did not allow dubbing from VHS to DVD. Also you have the issue of copy protection in a lot of VHS tapes. Google VHS Macrovision if you want to know more about that.
We have a 2012 Magnovox VHS/DVD combo. I understand it doesn't have a tuner. I was wondering if I could play a VHS tape and record it on a blank DVD? And then connect it to my flat screen TV to watch?