regular black pepper or course ground pepper. what taste better?

Pepper has a "bite" to it. Coarsely-ground pepper will have more of a bite. So if you like that hot taste, you will want the more-coarsely ground pepper. Fine-ground black pepper has less bite because you are not biting down on a small check of peppercorn.

I have a pepper grinder with Tellicherry black peppercorns in it, and that is what I use most often.

I also have one with mixed peppercorns in it, which I am more-likely to use with chicken.

For steaks, I don't use salt or pepper ... I use "Montreal Steak Spice" instead.

For white sauces, and some oriental dishes, I prefer ground white pepper.

Freshly ground black pepper.

I buy pepper whole and grind it course in my pepper grinder. It tastes way better, much fresher.

There are a number of peppercorns and you can grind them to any degree. If doing it yourself in a mortar and pestle, just either stop or keep going. When buying them, you choose between a number of mesh. A low number can come out pretty much halved corns, higher numbers are get-in-your-eyes dust.

The effect is about diffusion. Super coarse grinds are good for steak where a big pepper crunch would work and smaller ones are good for stews and soups where that would be disturbing.

Use course ground.