my fingers are beginning to cramp up from you! LOL! J/K, this is fun, not to worry (especially since i know the answers!).
To be 'obese' you have to be 30% over your maximium recommended weight. There are charts for this, you might google them and type in your height and it'll give you a 'recommended' weight range. 175 @ 5'8" doesn't sound obese to me.
It's good that you want to lose the weight, you'll feel better, look great, and live longer. Eating right is a good start, you're doing all the right things now, avoiding yucky McD's, eating veggies and salads, and exercising. Keep it up!
There is no 'maximium' you can weigh, go look around the next time you're in public, it's really gross how people let themselves go (especially in the summer when they give themselves permission to show more of themselves in the name of 'comfort'...ewwww!). however, with proper nutrition, a sensible, consistent exercise regimen, you'll hit what's called your 'set point' or 'sweet spot', which is a pretty consistent weight for yourself.