You know I've had a lot of colors as my favorite through out my life.
I barely remember playing NFS Underground 2 on PC as a small child (I believe I was 2 years old at the time, turning 19 in less than 2 months), when I was playing it I painted every car I could pink. It wasn't in career, I didn't know career mode existed way later in life.
Infact I believe it was the first NFS I ever played. The second NFS I played was Hot Pursuit (the one just before Underground 1).
Though I don't remember which color(s) was my favorite after that, I do remember that during final years of kindergarten it was green.
In early school years this turned to neon green, which changed to neon orange, which changed to neon blue.
In my final years of school and during high school I started to like black a lot. Well... just just black, white as well, along with shades of gray.
But I don't really like solo colors other than black. White has to be accompanied with black, and so does any other color.
Anyways That's about it.