If you know your SE account name and password, you can log in, go to services, FFXIV and reactivate. You will find it under your account management if you dig around in there. Reactivating is easy. As for reinstalling... either get Daemon tools and find an online CD thing. Or 2.0 will have trials so I assume electronic download (FINALLY!). I would just wait and see because most likely there will be 2.0 electronic download.