Q: Just got an iphone 6s. My old iphone is backed up on computer. Plugged the new phone in and my iOS is too old to recognize the 6s and my computer is too old to download the new operating system.  How do I configure my old phone?

Did you by chance do an iCloud back up at any point?  That will help

Using iCloud to Backup & Restore

Backup

http://support.apple.com/en-us/HT203516

Restore

https://support.apple.com/en-au/HT201418

Apps were never backed up, only apps data.

lilmmatty wrote:

 

Pictures don't either?

Only your camera roll. Photos from the computer are still on your computer.

You should save any photos that are important to you to your computer like any other digital camera.

If you do not have access to another computer, you might try iCloud Photo Library.

iCloud Photo Library FAQ - Apple Support

You're welcome.