Hi Dicko
I think Japanese is sometimes over-used. While it doesn't hurt to learn basic terms it can sometimes be that some people use it as a way of trying to assert a superior level of knowledge instead of just getting on with it and demonstrating what they can do. Having said that, some time ago I put together a bit of terminology here:
http://kitsunekan.com/articles/stuff08.htmlBear in mind that different styles will use different terms for the same techniques, and also that different styles will have the same names for a technique but the technique will be done differently (sometimes markedly so!).
The advantage to learning at least some of the terminology is that you begin to see the way the names of techniques are structured and this can let you work out what sort of (unfamiliar) technique someone is talking about by the name. For instance "age" (pronounced ah-geh) usually means "rising" so "age uke" is (loosely) a rising block, "age tsuki" is a rising punch etc. I say "loosely" because I feel "uke" (oo-keh, though you'll probably hear it more often pronounced yoo-kay, and you should consider slapping the one who says it) is usually interpreted as a blocking action (implying force) rather than a receiving action (which doesn't always mean it requires force). It would be more correct to interpret "age uke" as "rising receive".
As you know, "rei" means "bow". You could look up "reiho" which roughly means "etiquette", so you can see the connection. You say "hai" for yes, others use "ossu" (sounds sort of like "oos", with "oo" as in book). The rest of us just use "yes" or "okay". Why? Basically because the Japanese terms are something you can learn if you're so inclined, and something you'll inevitably pick up over time, but generally I'd prefer students to spend their time practicing techniques than learning all the terms.
Train, practice, learn more about what interests you, enjoy it, and fire away with any questions on the forum here. There are plenty of people who have answers, and even a few with good answers

but all have been where you're at and understand how much there is to learn.

Mick