depends on the group. in a party setting i'd go for something quick like skull, tsuro, or cockroach poker.

if people want something light i'd bring codenames, or coup, or azul.

i love co-op so if everyone was down i'd bring space alert, earthborne rangers, or mind mgmt. maybe even captain sonar if we could get a big enough group.

root, ark nova, or terraforming mars are all great for a board-gaming group but may be a bit heavy to drop on people who just want to hang.

if you really want to scare people you bring high frontier.