Bring the TV back unless it also has composite video input(one RCA video in, 2 RCA audio). The Wii can be connected via component video (according to the Wii web site)
using the cable that comes with the Wii but you need it for the DVD player.
Like I said -- return the TV and spend a few bucks more for one with more than one component video input or has composite video;
Buy a blu ray player and connect using HDMI (and probably have to buy an HDMI cable unless you get it at Costco which many times includes a HDMI cable). Forget the DVD player if you do this. A blu ray player will probably give you a better picture with standard DVD's than a HDTV (most of which don't do standard definition real well);
Make a choice between Wii and DVD or unplug one and plug in the other if you want both.
I just bought a new LCD tv. It has one set of component plugs and 2 HDMI plugs. I currently have my cable box connecting to my tv with one hdmi cord. I then have my DVD connected using the component plugs (green, red, white plugs). I have one HDMI plug left, but cannot get my Wii to connect that way. Is there a different way to hook up my DVD player? The DVD does not have an HDMI plug on it.