What does full open bar mean?

I would think it means open as much as you want to stock. What you buy and serve is totally up to you! i'm having an open bar too, buying all the stuff. I"m not buying everything imaginable though, i'm buying a beer and a lite beer, white wine and red, some champagne for the toast, and probably some vodka and whiskey. Not sure about anything else. Rum maybe.

A full open bar means that all selections of alcoholic/non-alcoholic beverages are present and available. You may want to address yours as a "limited" open bar so you don't have to overextend yourselves making sure you have all the different offerings available (though I don't think your selection is limited, by any means!).

A "full bar" means you carry a wide range of spirits. Hard liquors, beers, wines, liqueurs, etc. An "open bar" means that you are paying for everything and your guests are free to drink without paying.

You are having an "open beer and wine" bar. It's a great choice for weddings. You'll have more drinks available because your budget goes farther when you exclude hard liquors and liqueurs. Also, you are less likely to have friends and family over-imbibe.

I would say yours is a limited open bar just because you will have one selection of each wine, and one each of 4-5 different liquors. Your beer selection is right on point! The top shelf isn't necessary, like for instance my venue obviously charges more if we wanted to pick that option but we are just doing basic liquors. If you are providing it yourself, a basic Kettle One vodka is good. I wouldn't go lower quality than that lol. Full bar would mean there is more things like mixers, different garnishes, more than one choice of something.

Full open bar means unlimited beer & wine & hard liquor, whatever is available at the venue.

You definitely don't have to do top shelf, that's usually an upgrade at most places. I would say what you have sounds appropriate... a vodka, a tequila, a rum, a gin, a whiskey... rail should be fine but I would also say "know your crowd"... that should cover just about anything someone might want to drink.