I have 2b/2c hair and I've probably dyed it 40 or 50 times...
My advice is to use Revlon Colorsilk. It's the cheapest dye AND it leaves your hair in great condition. The expensive dyes are the reason my hair has been totally friend and damaged. Colorsilk works really well, in my opinion.
However, make sure not to dye his hair too often; if you must redye it, do only the roots.
Hope that helps! Let me know if you have any more questions... I'm not too sure how many ladies here have type 2 hair. Is there anyone else out there???