"What is the difference between tridentine and indult? There are two latin masses? I've never been to either"
Yes - there are two Latin Masses. The Mass as it was prior to 1962 (Tridentine Mass) may only be celebrated in Latin. This is also known as the "Indult" Mass, because it may only be said licitly by virtue of an indult (special privilege) contained in the Pope's motu proprio (a bit like an apostolic letter) called "Ecclesia dei".
The new Mass (Novus Ordo or Missa Normativa) may also be celebrated in Latin at any time by right. However, it is nearly exclusively said in English or the vernacular language of the country concerned.
If you've never been to either, I would recommend that you do, as it will at least give you the sense of our common heritage. You will feel more of a link with the roots of the Church and a communion with all our glorious saints and martyrs from whom we received the faith. You will experience how the Church transcends both time and space.
Ideally a sung Latin Mass or High Mass would be best to try if you can find one.
Not to mention being at the same Mass at which your grandparents, THEIR parents, their parents' parents, etc., for about 80 generations back.