How do I reset my phone?
Does this wipe photos/contacts etc?
Is there a deafults option?
Thanks.
edit: Will a factory reset bring me back to jellybean?
Yeah it will wipe absolutely everything. But so will a downgrade to Jelly Bean.
Files on your SD card will remain but I would take it out before you reset it just in case.
Contacts should be sync'd to your google account?
The only thing I've needed to do after a hard reset is download my apps again. You can backup your SMS and Call log using an app on the playstore called Super Backup.
To do a hard reset:
Settings > Backup & reset > Factory data reset.
A factory reset will just wipe all data on the ROM you're on. If you're on Kitkat and you do a factory reset you will remain on KitKat but all data will be removed (apart from factory data/apps). If you're on JellyBean and you do a factory reset you will remain on JellyBean but all user data will be wiped (factory data/apps will remain).