Snails are easy to remove if you overfeed and get too many. Simply blanch some spinach or lettuce and put in a leaf in the tank overnight. You can weight it down with a rock if you need. By morning or sometimes within an hour it should be covered with snails. Remove the bait food and repeat as often as possible until you have suffiiciently reduced the population.
As for recommendations, I really like malaysian trumpet snails. They will mostly hide in your substrate and come out in the evening and feeding times. They will take care of some algaes and the remaining food in your tank. You must be careful not to overfeed the tank or you will see their numbers increase. These are not the prettiest snails, but they are a great maintenance snail.
You can also consider ramshorn snails. These guys lay eggs on the glass and on plants and other objects which you can typically see. You can scrape eggs off of the glass as a means of population control, but again...don't overfeed.
Both of the above snails you can typically get for free from your LFS. Their tanks are overflowing with them and you can simply ask for some of each kind for free.
A third option is a mystery snail. These are really lovely snails that come in many colours. They can grow very large and their numbers are easy t control as they lay their eggs in a very obvious and large clutch above the water line. You will be able to see it and remove it easily to control the population. I am not suggesting this for your 5 gallon as mystery snails can be very poopy, thus polluting your water. You will need to be sure to stay on top of your water changes weekly. If you can upgrade to a 10 gal, mystery snails would be a more manageable option. If you decide on a mystery snail for your 5 gallon I would not house more than two. They will eat the excess food and some algaes.
