Well first off welcome to the HQ............. :beer:
As far as octane Yamaha recomends runnin' at least 93 octane in your quad, and if you do a compression check and you are above 160 psi, you need to run AV100LL (ie aviation fuel) or race gas. The higher the pressure the higher the octane you should run to keep the motor from detonating (ie pinging).
Most people on here run 32:1 with no problems, and yes everyone has there fave's, but just get a good brand Motul, Castor, Klotz, H1R, take your pick and stick to it. Don't change around because a different brand was on sale that day............
Others will chime in here with their .02, so take the advice and figure out what you want to do. Welcome to the money pit from hell by the way (Go fast goodies, you'll never have enough power )