HD set up problems

I have an older HD ready Mitsubishi HD ready tv - model Ws-65807. I have a Direct tv HD receiver hooked up to the tv and just bought a LG BD390 Blue Ray player (being able to stream Netflix movies is a nice feature).

I am concerned that I will not be able to get HD quality for both my Satelitte programing and DVD player.

As of now I have component cables running from my HD receiver to the tv. On the TV there are a group of input jacks for standard VCR, laser disc and other A/V devices per the manual. to the right are more inputs under a label for High Resolution Input. Under this label there are two sets of jacks for component cable with the marking 480i/480p below the component label. Then there is another section of inputs under the High Resolution input that are under a DTV label with 480i/480p/1080i markings by the label. As of now this is where I have my HD receiver hooked up to, there are three vertical inputs labeled YG, PrR, and PbB.

I called Direct TV and someone said I probably should get an external box where I can switch between HD tv and DVD.

I am hoping for another alternative. There are also two video out jacks on the back of the HD receiver a V1 output and V2 output. Under the DTV label of the tv (which is part of the High resolution input jacks)there are two inputs, one labeled H to the right of it and the other labled V to the right. When I checked the tv manual there is a section for input levels and timing when used with rgb video signals and for both the V and H inputs it shows an = 3Vp-p/1.0v, 75 ohms.

I do not have a clue what this means but I am hoping I can hook up the HD receiver to one of these jacks and still get good resolution for HD programing and hook up the BD390 Blue ray player to the G, R, and B jacks, if that makes sense.

I would rather make quality sacrifices with the HD tv programming than for blue ray DVDs.

Thanks for any suggestions - Gary