Just the languages, please. Less text, more interface.
The more text you try to include, the longer it will take visitors to find a page that really introduces them to WP; and the longer it will take to add new languages; and the harder it will be to generalize to other Wikimedia projects.
http://www.europarl.eu.int/ is a fine start. Add another two-column list in smaller font for the next 70 languages, and perhaps a big >> arrow at the bottom leading to a full list of all langs or a dropdown menu for the smallest 100 langs.