I use a Samsung S5 (Globe LTE) which has a fingerprint security system, but I forgot the password, and I can't use the fingerprint anymore. What should I use? Should I do factory reset or hard reset? Also, my phone is lagging.
"Factory reset" and "hard reset" are just different names for the same thing. Just make sure you know the password for your Google account, as you'll need it after you factory reset.
You may try PUK code ( located on SIM card ) to unlock if tried too many attempt of pin. But I'm not sure it works or not in your phone model.