I've looked at Nanoid Backup. You're better off to do you nanoid backup from within recovery. Which custom recovery are you using, TWRP or CWM? I haven't used CWM in a long time, but with TWRP, you simply go into recovery mode and TWRP presents you with 6 or 8 buttons. One is Backup and another is Restore. Press Backup and the next screen (read it over), gives you some options, like what to backup (I check all of them, including cache and recovery). Note where it will backup to (internal or external SD) and change as appropriate. Backups can be large depending on how many apps you have installed. I keep the latest backup on my phone and transfer the previous backup to my PC, just in case. One of the other buttons in TWRP is Install, that's were you install any roms or mods that are of the .zip variety. Another button in TWRP is Wipe. Before installing a new rom, it's always best to do a Factory Reset, wipe cache and davik cache. Depending on the rom you install and the rom developer's instructions, sometimes you can update the rom you have installed by doing what's called a dirty flash, that's just wiping cache and davik cache without the Factory Reset. Again, that's at the discretion of the rom developer and even then a factory reset will result in better results if your phone starts to act flaky.
On the subject of Titanium Backup, yes, you should backup apps first, it's like an added layer of protection and after a factory reset, it's a good way to restore your apps plus the data stored with the apps. If you choose to let Google restore apps after a factory reset (which some people say is the way you should), you won't have any saved data with the app. You can though, restore data only from Titanium Backup to get data back. Another great feature of TB is the ability to create an "update.zip" file of all your apps and data and flash that right along with your rom (TWRP allows you to install multiple .zip files, one after the other). That way, when you reboot, all your apps are already back. I've been told that unless you have the paid version of Titanium Backup, you are prompted with an Install Y/N prompt after each app. I have the paid version, so can't speak for certain.
Last subject, assuming you haven't installed a rom yet. The first boot may take as much as 15 minutes to boot up (It may take 2 hours if you stare at the screen
). Be patient, I walk away for awhile.