[T-R]

I'd definitely go for the classroom. Unless you're living in the country, it can be pretty hard to maintain the discipline to cram vocabulary at a reasonable pace without anyone checking on you. Also, at some point you'll at least need someone to practice with, ask questions, and check your grammar.

If you're looking for tips - when I was taking multiple languages at once (Japanese, Chinese, and Korean), between classes I listened to music from the language of the class I was about to go to, to get my mind switched into that mode. I'm also under the impression that the music helped with my pronunciation a lot (but not with listening comprehension as much as I'd've expected).