If the rust isn't pitted, use 0000 steel wool saturated with a good gun oil. Don't scrub in one spot, do long areas all in one motion with a light pressure. The idea is to let the steel wool and oil break down the rust without removing the Bluing. Don't store any gun in a soft gun case, they absorb moisture and will rust a gun right quick. You can paint it if you like, but to a lot of people it devalues the gun. Putting paint on a rusted gun is just covering up stuff. If you intend to keep the gun, it doesn't matter. If you are trying to make it look good to sell, you might find someone to buy it with a cheap paint job if the price is right but would be better off trying to remove the rust without destroying the bluing.
This is very good advice. If the gun is blued (not sure about a Maverick) This is the best way to remove light rust. After this treatment ($3 for 0000 steel wool) if the blue is gone in spots, you could try some cold blue ($6). To me, this would be best. Sanding and Krylon will work, and even look good, but it will be pretty fragile finish.
X2 on NOT storing guns in soft cases!! Have seen blued guns nearly destroyed from spending 6 months in a soft case in a closet!!