I know a special designed android data backup app, just few simple steps to transfer everything from your phone to computer, and you don't need to root your phone, just need enable usb debugging on your phone.
http://www.android-file-manager.com/
Thanks to the default Backup & Restore feature on the G2, you can easily create data backup from your files, settings, and apps, and restore them later.
To backup data on LG G2 do as follows:
1. Open Settings and go to General tab
2. Under Personal settings, open Backup & reset
3. Open LG Backup service.
4. Tap Backup and then select the items you want to have a backup from
** Available items to backup are:
i. LG Home Screen: LG Home
ii. Personal Data: Alarm/Clock, Bookmark, Memo, Notebook, Calendar, Call log, Contacts, Message, and Voice Recorder
iii. Media Data: Music, Photos, Videos, and Doucments
iv. LG Apps: Dictionary, E-mail, FM Radio, Tasks, Update Center, and Weather
v. Downloaded Apps: The entire installed apps and settings
vi. Settings: Wi-Fi, Call, Sound, Display, and Accesibility
5. Hit Next, set password for backup, and then hit Start to start the backup process
*** To restore the backup files, Go to LG Backup and then tap Restore and select the backup file to be restored
*** You can use Scheduled Backup to create backup at specific time frames
Lean More LG G2 Tips and Tricks