Never synced with PC...how to transfer data on iPhone to PC (iOS4.1)

Hi~

Friend of mine wants to backup his data but never synced his iPhone 4 (running iOS 4.1) with his computer (PC).

When I connected the iPhone to PC, it asked me if I wanted to upgraded to iOS 6.

I'm a MAC user and not familiar with PC...

How can I backup the iPhone 4's data (Contact & Note) to PC? I tried a contact sync program but was limited to only 50 contacts for free.Regarding Notes, it asked me if I wanted to sync with outlook, google or windows... I use neither.

If I check "sync app, contacts, notes" will it replace the iPhone data with data from PC which there is none?

Botton line...
Want to transfer iPhone 4 data to PC and upgrade the iPhone to iOS6 without losing any data.

Thanks in advance...