According to the DVDCV51 manual I found online the player does not have an analog VGA/RGB output. It only has composite, s-video, and component analog outputs. The TV only has composite and VGA/RGB analog inputs. So, I'm at a loss to see how you connected using the 'RGB video9' unless you used some sort of converter cable which will not work if the cable is 'passive' - just wires with different connectors on either end. You need some sort of electronics to convert from YPbPr (component video) to RGB video.
How does it work when you use the composite video and L/R audio - the ole yellow/red/white cable?
Also, since you got a nice windfall of a 46" 1080p TV, you might want to consider getting a Blu-ray player if you can afford it. You can get a Blu-ray player for well under $100 and you'll be able to take advantage of a high-def digital connection to the TV. You'll also be able to play Blu-ray discs in addition to DVDs an have much better picture quality. And with HDMI, both audio and video are sent over the same cable - just one connection!
Opportunity is missed by most people because it is dressed in overalls and looks like work. -- Thomas Alva Edison