New "old" bike run through maintanece Q's

[Pushdeck1]

So I picked up an 2000 GZ250 and have an Idea of what to go through but thought I would run it by you guys to make sure.

1. New Gas, Drain old (What octane should I use? 87,90,93)

2. Clean or replace air filter

3. Change oil (says weight on cap, does it need to be motorcycle rated oil?)

4. Tire Pressure (says 40 cold but I know that is too high, hear 25 Front, Rear 30ish?)

5. Chain is loose (any words of wisdom before tightening?)

6. Check Brake fluid

Anything I am missing? :??:

Thanks for the help in advance!