Can Best Buy accept my iPad mini (2015 ) and MacBook Air(2010 ),for a new iPod 32G for part of a payment?Is there any way to transfer pictures and contacts to new iPod?

You can bring the items to the Customer Service at Best Buy and do a Trade In. I'm not sure what the value is but they'll let you know and can put the amount on a gift card or store credit that you can use towards a purchase.

Hello Alex, not sure on how Best Buy accepts or if they accept part of a payment for anything unless you have a credit card account with them. As for the iPad and iPod you can backup all data to iTunes and transfer it to anything that has to do with Apple.