How do you import an object from another Blender file without losing textures? I built an LP Record in another Blender project (including colors, textures, images, materials) and tried to bring it in to my current Diamond Head project: 

I appended the Diamond Head project with the LP object. I got the disc shape rendered in gray. So I tried importing the Materials and Nodes to no avail.


My objective is to have the record spinning in the crater, so I need to merge the two projects. What's the best way, if any, to accomplish this?
Use a consistent set of materials for a Render engine.  Cycles Render or Blender Render.   Do not mix Cycles and Blender materials.

It appears you have tried to mix materials for the two different render engines.

If you are producing a single still photo you may be able to render one image as transparent .png file.  You may be able to render the album disc as a texture and apply it as .png which is render engine neutral.