How did they make this?

[Asjemenou]

Ok, I like to take it a step further:
Image I have an collage made like the attached one and I dont want tekst on the side like in a menu but that you accualy click on one of the pictures inside the pictures.
The show black and white but when mouse over and click on it they change to color.

Can that be done the same way as I did my beta or is there an easier way?