I just recently finished my PADI OW Confined Dives - and I will tell you that I too was very scared about removing my mask underwater. Before I went to the classes I even asked if I bought a purge valve mask, would I still be expected to remove it underwater. Of course, they said yes.
To be completely honest with you, it's now like second nature, and turned out to be the most useful skill I've learned, instead of the horrific experience I thought it would be. Even when snorkeling or free diving now I frequently remove my mask of flood it to de-fog it when it gets bad underwater. It takes about 3 seconds and is extremely easy. There is no way to get it across to you until you try it - but I can promise you it's not nearly as bad as your mind is making it out to be.
As far as removing the equipment underwater, it was pretty easy, also, to be honest. Not much finesse required, just a little balance so you don't drop the scuba unit once it's off your shoulders.
The hardest parts of the class - as far as I was concerned, was the fin-pivot neutral buoyancy excercises (my buoyancy is not so great yet), and the OOA.
When I felt the instructor turning my tank valve off I hit a brief moment of panic before I got a hold of myself, and I was in 8 feet of water. But even then, I took the last half of breath or so, gave all the appropriate signals, and surpisingly, I did not end up panicking at all, just calmly asked for share-air and waited for my air to come back on after giving the OOA signal.
All of the big things that people told me were super hard ended up to be actually a lot of fun. I was super worried about breathing from the free-flowing regulator also, but that was one of the best experiences, as the Instructor I had was very fun to work with.