Organizing a game night with non-gamers?
Depending on the size of the group and the time allotted:


Get games where people do not loose, though people can win. E.g. everybody keeps playing until the end and the player with the highest score wins.Not a game where people get killed and then have to watch the rest play for another 4 hours. (Titan, I am looking at you).
Do not get uber long games. E.g. no Titan, no Doom, the board game, no eclipse (the game can be short, but NOT on the first time you play it).
Start with relative easy on-complex games to start with. E.g. Alhambra. Of if you play Catan make sure it is the basic version and not the game and the Cities and knights extension.
Get a few short games to fill time gaps. E.g. bohnanza or Der Schattendieb.
If you have 7 or 8 players consider running to games simultaneously. E.g. thurn-and-taxis (up to 4 players), basic catan for those who never played it before starting on a more complex game, powergrid etc etc.
Last but not least, consider a few non board games for variation. Machiavelli can be played with a large group.


On games nights I also like to pre-arrange food. Usually with some short games while people arrive and the cook (mostly me) cooks, then dinner, a clean table and some games. Add some non-greasy snacks.