I would use Chrome tape... only 2-3 songs AT MOST.... best song first.... better still, try a collage of song snippets (unless you're shopping the whole song itself!)
I would put Dolby B ON.... here's why... people will play on 2 kinds of machines - a better quality one that has Dolby enabled on it anyways, or a poorer quality unit (or boombox) that doesn't....
With Dolby on, the recording will be quieter on the better units... on the boombox, sound quality will already be questionable and the recording will probably benefit from the added high-end boost of a Dolby-encoded being played back with Dolby off...!