Hey mate, those sizes you mentioned will fit, but an important factor is also depends on the offset of the rims you buy. If the offset is too positive (wheel goes more towards the car, eg. +50), a wider wheel may/may not fit or scrubbing may occur. For the ZREs go 17x7s, 17x8s, 18x8s etc with offsets between +35 to +38. Before you buy the rims, should make sure by having a 'trial fit'. :) In regards to tyres, there are heaps of tyres out there depending on your needs/wants, thread pattern, how deep your pocket is etc etc. Generally, the wider the tyres, the more grip and the more stable the car is. However, too wide/big and you may experience more drag, more fuel consumption. For what size tyres to get, use this TireSizeCalculator. Try get a tyre size that has less than 3% difference compared to your stock wheels. This ensures your speedo is not out of whack when you put on your new wheels/tires. :)