The first bike you posted would be a great commuter with a rack and fenders. Rigid fork mountain bikes are early 90s, so the asking price $150 is high - you should offer $100 and be prepared to pay a bit more. Buy a few tools, pump, patch kit, tire levers, spoke wrench, cone wrenches, hex key set - then go to the Sheldon Brown or Park Tool websites to see how to use them. I used to commute from Finch/Islington to Downsview in the 70s and early 80s. Good luck.