Maximum PC

I am looking to create a home network/backup service with my existing PCs and hardware - hardware listed below. The core function I want is the sync my docs, videos, pics, between my computers and be available to my iOS devices (2 iPhones and 2 iPads). Ideally, I would also like a separate back up drive to back them up incrementally and keep track of past changes. In a perfect world, it will sync with my dual-boot Hackintosh as well as the other side of Win 7.

Essentially, I want a "Dropbox-like" syncing ability that works off my Synology server and syncs my computers and is available to my iOS devices.

Any ideas on software to set this up? Did I miss something in the Synology software that can do this?

Hardware:
Synology DSJ 211J - 2 drive bay
Toshiba Laptop running Win 7
Desktop - Win 7, i7 3770, 16GB RAM, 3TB HD, 256 SSD
Desktop - Hackintosh w Mountain Lion - same specs as above (dual boot)
2 x iPhone 4
2 x iPad

Thanks for the help and pointers.

Not sure about IOS devices but all you need is a server with file sharing enabled and a syncing program on each PC. I use Cobain Backup 8 myself with no issues for over 3+ years.