jQuery 1.9 removed a lot of older features that had been deprecated in previous versions. Moving from jQuery 1.2 to 1.9, you are almost certain to hit quite a lot of them, as you've found.
Fortunately, jQuery 1.9 has a companion library called jQuery Migrate for backward compatibility with older versions, which puts back all the old deprecated features that were removed in 1.9.
If you need to get your old code back up and running with the newest jQuery version, use jQuery Migrate to get it working.
However, bear in mind that the purpose of the Migrate library is to help you make the transision to the newer features, not to allow you to leave your code stuck in the past. So use Migrate to get the code working, but then you need to start looking at changing your code so that you don't need Migrate.
Depending on how much code you have, that may be quite a bit of work, but having Migrate there allows you to make those changes one-by-one, rather than having to fix everything at once.
Hope that helps.