You can't really go wrong with a 686, assuming it's new or as new and hasn't been messed with. If it's used, get someone to check it over, as timing, cylinder shake, chamber alignment, and other issues are not something you will be familiar with. Not sure which 686 you are looking for, but there are plenty of models. For a first time shooter, get a 4" or 6" barrel 6 or 7 shot (seven shooters are newer and may bring a higher price). My favorite 686 is the 7 shot mountain gun, but unfortunately they don't make them anymore. The six inch barrel is a little front heavy; I would definitely suggest the 4" for general use.
If you're looking for a carry gun they are one heavy sucker to wear all day; you can pack a lot more ammo in a lot lighter gun, but it sounds like you're new to shooting, and carry probably isn't an issue. If you are getting your first handgun, it should really be a .22 rimfire; ten thousand rounds later you will know a lot more about shooting and with the money you didn't spend on ammo you can buy several centerfire revolvers. If going to shoot mostly .38 specials, also look at the 66, with a slightly smaller frame. You might find it does all you will ever want.