Choosing a model.

Yes, to all your questions.  And the Zip manual thread/manual link, for your questions concerning the device:  http://forums.sandisk.com/t5/Sansa-Clip-Zip/Clip-Z​ip-User-Manual/td-p/242618.

Also, I don’t know that I really would consider the battery in the Zip ‘weak":  12-15 hours of play, when new.  (But, yes, the Sport’s battery lasts longer.)