Site Colors: Your Thoughts

I am creating a new site for class that has to deal with a controversial topic, and I decided to go with stem cell research.

The site will be amazingly simple. There is a plate, if you will, of empty cells. In a small row in the middle will be six or seven colored, or differentiated cells which correspond to a page on the site. When you click on the colored cell, the blank cells around it will turn the color of the selected cell, expanding outward until the page layout has been created using those cells. When this happens, the colored cells which weren't selected fade to gray, except on rollover when they show their true colors, in an attempt to tone down the site a bit. Take a look at a screenshot to better understand what I am after.

The question is, I need colors for the various sections, colors that are both separate but also part of a family. If they are too similar, I am afraid people might not understand what's happening when the cells around a selected item change color. If they are too different, it gets to be an eye-sore. I have placed a few options I have looked at, but if you have better color suggestions, I would love to hear them.