potatoe question

Yesterday I dug up my spuds and was reasonable pleased with the crop. I grew 3 types - forgot which as the seed bags I staked into the ground have faded beyond reading.

My question is - one type produced lots of what looked like green tomatoes which hung from the top of the plant and then fell everywhere. What are these for? Do I have to pick them up and if not do I risk them producing spuds next year if I dig them into the soil? can they be composted or will they start to grow more spuds?

Potatoes are closely related to tomatoes and these are the seed heads.  Just compost them as normal but don't be tempted to eat them as they are toxic.   

You can, in theory, grow spuds from them but it just isn't worth the time and effort.