Renewal in 2 months time, i'm 19, will have 1 years NCB and i have a 1979 VW MK1 900cc Polo L, i've had it insured third party fire and theft @ £640 as the named owner and driver of the car.

What should i expect or be looking for?

Wondering whether u think its worth putting it full comp..

I'd go fully comp, it's not usually that much more. Try get a quote online, then amend the level of cover at the end for TPFT to FC.