How to transfer files from iPhoe to PC?

So I have an old iPod that I oly use to store my new music on, and my iPhone which has my old music on it and all my apps and stuff that I'd like to keep. Once I tried to sync my iPhone to my iTunes and it erased everything i had on it. I have everything backed up to iCloud just in case, but what I want to know is if there's a way to take the files from my iPhone and put them onto my computer so I can sync all the old content AND new content onto my phone so that nothing at all is lost? I'd really like to add old apps and music but I can't spend time and money downloading all the old stuff I had before back onto it ugh. If anyone knows a program that'd be great.

I have this problem! I have an iphone and I wanted to copy some files from my phone to my laptop so I could save some memory, but I don't know how to do it: because copying and pasting them from the phone doesn't work.