Brakes probably need to be adjusted. The fluid will come back up if it's low once the adjustment is done. It probably wouldn't hurt to flush out the brake system if it's been sitting a while. Check the condition of hoses & the res. That'll likely be under the front hood where the spare tire goes.
The sounds, like you said, is likely because it's old. The muffler or other exhaust components might be rusted through in spots. Easy to replace, though not the cheapest thing in the world.
The carb might need adjustment, a filter change or the lines blown out. There may also be rust in the tank making the gas impure.
I'm at work, so I can't search links for you for the brake adjustment, but there are tutorials all over the web & YouTube for that operation.