You can install a CyanogenMod ROM if you want. That way you can install new versions of Android like KitKat. I've installed it on my mobile (after it went out of warranty and not being supported by the distributor).
Yes it is very possible brick your phone while flashing a rom. More likely than not that you will brick the phone several times and resurrect it using the occasional heaven-sent XDA forums post, before you finally flash the rom if this is your first time.
If you have rooted it, I suggest setting up a google drive/dropbox account where you have a folder labelled android. In this folder you will store EVERYTHING in your current device. Download App Monster from play store and backup your apps. Don't store any backups you have made on your phone, store all of them in that online backup you have set up.