Jargon/Vocab about variables--- yes or no?
Some of these words are entirely necessary, some (such as tokenize) you might want to avoid early on.  However, I would suggest this as a guiding principle: use vocabulary as is necessary to get at the core goals you hold for your students, but do not emphasize vocabulary for its own sake.  A great visualization or metaphor at the very start (after all, freshmen!) will take your students much further along than a series of fine distinctions.

Here is a fun little article about 10 Extremely Precise Words for Emotions You Didn’t Even Know You Had.  The title is correct; when you read through the article, you will find emotions that you have experienced, but never described.  Nevertheless, you were able to experience the emotions perfectly fully. 

Similarly, with the help of a great diagram or metaphor, students will be able to utilize concepts that are more advanced than they can fully describe.  That's okay - great even! - and later coursework can help them nail down finer distinctions as they advance.