If you've not used one before, and you're comfortable with the price (they have come down alot recently), then trust us - an SSD is one of the greatest changes any user can make to their system. A simple google on SSD benefits will give you all the reasons you'll need.
Of course !! ( ) put your OS on it and, with c240GB you'll be able to put all your development utilities in and have plenty headroom for other things e.g. Office,games,etc. Never fill to >90% capacity (they need space to work efficiently).
@mesab66 and @AMD Radeon thanks - i think i'll definitely go with an ssd.
so many choices on all the components it's crazy. but one last question (maybe last question). @AMD Radeon i agree with the 2 monitor solution, but a little hazy on requirements. can i just use the mobo and cpu or do i need one or more video cards?