ads spiral inductor

I am designing a mixer to operate at 2.4 GHz.. and have an inductor that has to be grounded in the matching network...since I am using microstrip i know i'll have to drill a hole to connect it to ground but...is spiral inductor the best route to go or an air core inductor which i'll have to wind myself...also when designing a spiral inductor in momentum,,, I define the substrate as: free space ->air(10 mil)->dielectric(εr=2.2) ->///GND///...now this is supposed to represent the metal for spiral turns(in the cond layer below free space), the under pass(above the delectric i.e. cond2 layer), and the air layer between them is meant for the via( in the resi layer) to connect these two....am I doing this right? and what about the dimensions of the via and underpass metal to connect the centre of the spiral to the next component or line and what kind of a metal via shuld I use...circular or what....and also when i have to ground the inductor which follows a capacitor..I think i should connect the centre of the spiral to the capacitor and drill a hole and connect the outer most line of the inductor to the ground in microstrip...will that be alright? any help will be appreciated...thnx