[NTG-context] switching to Context

Hello, I'm thinking of making the switch from latex to context, indeed I'm working on my first non-trivial document as a trial. I have some questions. (1) Is it possible to do conditional compilation? I wish to use context to write lecture notes with embedded pictures. I'd like to compile the document into one form to hand out to the class (or make available on the web) and another to be used as a presentation, much like latex-beamer, with just the pictures. (2) Is it possible to convert context into plain text (i.e. strip out the formatting instructions)? This may seem eccentric but it might, with some programming, offer a means to put document content into a relational database, perhaps in paragraph chunks. Thanks, Roger