I always have matching tyres on my road bike...but at the mo I'm building a triarm for the track and I'm using nc29 wheels... I have a dunlop to go on the front and have come across a near new pirelli in my workshop, and I was wondering would it be ok to use these together or would it be a no no?

same brands is normalyl doable - but I would be wary of mismatched manufacturers. Profiles, constructions etc are all different.

Ok...Checked the tyre's and I've actually got a Pirelli Dragon Supercorsa 120/70 zr17 58w for the front and a Pirelli Diablo 150/60 ZR17 66w for the rear.... Would these work ok together?...Track use only.

Should do but the front will be super grippy compared to the rear...

You need you be using the front in warm weather and be capable of running in Fast.
090's are as good as anything for the track as good in wet too