I'm running OpenSUSE 12.1 and want to use Java Runtime enviroment v. 1.6. They ask for an ssh-key.
Which package should I take: the proprietary or the open source one?
How would you install it? Via the terminal or via Yast?
Which to use has been debated before - basically, it comes down to the fact that OpenJDK, though backed by Oracle, is a more heavily developed open source project while Oracle's JDK is more stable but is not open source, which prevents its inclusion in a lot of purist distributions like Debian.
To get to the OpenJDK (which actually includes its own JRE), try this:
Oracle's Java is a little harder to get to; this site documents the process fairly well. Because Oracle's Java is not in the repository, however, you don't get automatic updating.