tự sát: 183000000
tự tử: 13800000
Those are numbers of Google search results. Tự sát got more hits, so I suppose that's more common.
Really basic: Español, lingua latīna
Conlangs (current): tikolmil, llyffws, Arliks, dilir
(Website is at http://risteq.net/
if you ever want to visit. It's supposed to be in 4 languages.)