If you need a very fast adventure you can try The Fright at Tristor: http://en.wikipedia.org/wiki/The_Fright_at_Tristor

It was a very basic RPGA adventure for 3.0 but it's almost a non-issue using it for 3.5. I like to use this to introduce new players to D&D because it's pretty tropey and straight-forward as far as "ye old fantasy adventure" goes and it doesn't take a lot of time to get through.