The most important thing to get is a good mask, and the most important factor in the mask is the fit. Some people have faces that can take almost any mask, some people are close to impossible to fit, and most fall somewhere in between. A good dive shop employee can work with you to make sure that you get the one that works best for you.
The next most important purchase is the fins. The one wrong choice you can make is to get snorkeling fins, which will not have the power to propel you through the water with scuba equipment. After that, there are all sorts of arguments about the exact style of scuba fin to get. The arguments can get very contentious, and I won't get into them here. It won't matter for your scuba instruction.
As for a snorkel, ask yourself why you are getting it. If you plan to do some extensive snorkeling in slightly choppy water, go head and get one with a design that will keep water out of your mouth while you use it. If you just want it as a scuba accessory, get the cheapest thing you can get.
Any bootie you get to go with the fins will be OK. The only real issue is whether to get a lightweight one for tropical diving or a thicker one for more warmth.
As for brands, if you are getting these things at a scuba shop, it won't matter all that much. Most of the top brands have similar quality. Just don't go into a department store like Walmart and pick out gear that is designed to be a toy. I had a student start class with a set of gear like that, and neither the fins nor the mask made it all the way through the first pool session intact.
