i only want to migrate certain programmes from my old mac

i only want to migrate certain programmes from my old mac

i want all my contacts

but not my old emails

i want to keep all my old photos on my old mac and start afresh on my new mac

iTunes match totally messed up my iTunes and I've clicked the not renew option but i want my files back to how they were before i converted to iTunes match?

i don't understand how to properly use iCloud? can i just put all my files from my old mac onto the cloud and keep them there instead of migrating them to my new mac? is iCloud like dropbox where the programme stores the files on the computer as well?