Good place to grab some Mexican in town is a place called Roberto's Cafe. Bomb margaritas and decent chips/salsa.
Looking for a breakfast that'll keep you full all day? Hit up The Stove. It's like Denny's, but on overload. The portions are huge, but the pancakes are yum.
Decent BBQ is Angel's. Yummy honey butter and good, giant beef ribs.
I'm not a local but I've been to Mammoth so many times, I feel like I know some of the best places to eat!
Also, the Westin has a pretty good happy hour, but it is a tad on the pricey side - so just be aware of that.
The best part of living in Mammoth is exploring on your off days... Look around! The town is a lot of fun and it's a great new experience for you to try something different. Enjoy your time and maybe see you in line sometime!