How to reset my Denon DN-V210 DVD Player to factory default?

Hi Jason,
I have just bought this unit and have been using the menu recently. The only ways i can see to do it would be to either, (as you say) plug it into a HDTV, or navigate the menu blind and hope for the best. 
If you press SETUP on your remote once to get to the menu setup screen and then push the RIGHT navigation button 3 times this should take you to the system setup screen. Then push the DOWN navigation button 4 times and then push ENTER. At this point it asks you for a 4 digit password to reset the unit which is a factory preset, 5555, so type that in. This should then reset the DVD player to factory settings.
Hope it helps,
Nick