I just purchased a Sony CD/DVD player, model #DVP-SR200P. I assume that I've hooked everything up correctly. I get sound and picture. But, the picture is in black & white. What am I doing wrong? Is there something I can do to fix it?

SOURCE: SONY DVD PLAYER DVP-SR200P BUT IT ONLY SHOW IN BLACK AND WHITE ?

You have posted this in the Panasonic DMR-ES30VS section.
Please note which product section you are in before posting your question.

For the Sony DVP-SR200P there could be multiple reasons for it only showing in B&W.
Was this a recent problem, is this a new hook-up, has it always been this way?

1. In the setup menu there is a setting for Custom Picture Mode.
   Could someone have turned the color down?
   You can go to the setup menu and "Reset" the player to the factory settings.
   
2. How is this connected to your TV?
   Check all cables to make sure they are plugged in, test each one by unplugging it, and then plug it back in fully.
   
   If you are using a composite cable (1 cable yellow plug), be sure you have plugged it in from yellow to yellow.
   
   If you are using the component (3 cables red-green-blue plugs) hook-up, be sure you are using cables only designed for component hook-up, and have plugged them in correctly, red to red, green to green, blue to blue (Be sure you've plugged the red cable into the red video not red audio).
   
   Are the cables in good condition?
   No breaks, loose connectors, they weren't smashed under a piece of furniture?
   Have you tried a different set of cables?
   
3. Test the DVD player on another TV.
   Does the same thing happen?
   Did you "Reset" the DVD player?
   Maybe the DVD player is bad?
   
4. Find another DVD player and test it with your TV.
   Does it work OK, or is it black and white too?
   Maybe the connectors on the TV are bad?
   Is there a custom setting on the TV for that connection?
   On some TVs you can adjust the settings for each input (INPUT 1, INPUT 2, ....) maybe the color setting is turned down?