Under "Document Display Style", usually located at the bottom left corner of your screen, is a horizontal row of clickable circles. Some look solid, some look like wire frames etc. The one on your far right, when you hover your mouse over it, should change the words "Document Display Style" to "Texture Shaded (Ctrl-9)"

This is the display style that gives you the closest look to a finished render in the work window, with colors. Click that right half circle or click Ctrl+9 keys simultaneously, and you will see your display change.

You can then goto Edit>General Preferences, and a small popup window will appear. Click the "Set Preferred State" button here, and your poser will always open with Texxture Shaded style active. I usually make sure Ive got a blank workspace before I do this, by hitting the delete key while any part of the default poser figure the program opens with is selected and confirming I want that figure gone from the workspace.

hope this helps,

Logan