DVD-R writes data in a different way than DVD+R. Yes you can connect it to the card but if it has 2 channels and you also have a hard drive hooked up to it make sure the hard drive is on cannel 1 or 0 and that the dvd drive is on channel 2.
In the past it was the DVD-R that had the most compatibility with DVD players. Now they are probably about the same.
If you haven't bought one yet then I agree that buying the dual compatibility burner is the way to go. I don't know of any major manufacturer right now that only makes a single-format burner so a single format burner is probably old inventory and not supported by newer drivers. It's almost a guarantee that if you buy a single format that it will be the one that is not compatible with your setop DVD player(s).