Is it 'OK' to use the root user as a normal user?
Using your computer logged in as root all the time is like always carrying around all your keys, your passport, $5,000 in cash, that piece of paper with all your passwords written on it and the only photo you have of Flopsy, the adorable rabbit whose death broke your seven-year-old heart. Oh, and a chainsaw.

Which is to say, it's mighty convenient from time to time, because it means you can do whatever you want, whenever you want, without needing to go back home to get stuff or talk to your bank manager. But it also puts you at great risk of losing stuff, having it stolen (don't think that chainsaw will help you: you'll be streets away before you notice your wallet's gone), doing things you really regret later (impulse-buying plane tickets to Vegas while drunk), taking dangerous shortcuts (chainsawing through the lion enclosure fence because that's the fastest way to the pandas) and over-reacting (chainsawing your neighbour's car because his dog barks too much). And, when you think about it, mostly, you're just going to the office, going grocery shopping, hanging out with your friends. You don't need all that stuff with you all the time just for the convenience of needing it, what?, once a month? Once a week?

So, no, it's not OK to use the root account all the time. It gives you a tiny amount of convenience but puts you in a lot of danger. There's the danger of stupid mistakes having catastrophic results ("Hey, why is rm -rf * taking so long to run? **** I'm in /!"). There's the danger of acclimating yourself to the idea that all files are equal and you can just mess about with whatever you want, anywhere in the directory tree. There's the danger that any hack to your account is immediately a hack to the whole system, so now every single piece of software on your machine is security-critical. And even if you think you don't care about your machine getting hacked (after all, that photo of Flopsy is a real piece of glossy paper, not some ephemeral JPEG), I care about your machine getting hacked because then it's on the botnet that's mounting the DDOS attack against whatever internet service I can't access today.

Root is your spiderman costume. It gives you great power but requires great responsibility. It's there in the closet whenever you need it, so you don't have to wear it all the time.