Bicycle Mechanics - Noob road tire questions

I'm new to road bikes(but not bikes in general) and yesterday had my first road bike flat (not caused my normal wear, but rather a stuck pump). I repaired it and its running fine, but I have a few questions:

1. Do new bikes come with rim tape already in place? The Mavic rims my bike came with seems to already have "rim tape" I think. I can't see the spoke holes anyway. There is a black material that covers up most of the inside of the rim. Would that be the rim tape? I don't need to add any right?

2. The tube that came with my bike was an "ultra-thin" lightweight type. 700 23c. I replaced it with a standard performance bike tube 700 19-25(is that a range of width) that's not ultra light/thin. Does the tube thickness really matter? Do really thin tubes tend to get flats easier? Is the difference in weight something that is really a big deal? I am using this bike for commuting and want to make sure it doesnt' get flats too often, but also don't want it super heavy.

3. Is there a general way of knowing what are higher quality tires? Like specific brands? I know there is a thread count, but what about the kevlar and other additives? Anyone have suggestions on nice tires that are a great compromise of speed and longevity?

Hi SlumberMachine,
Answers to your questions:
1) yes rim tape will come with a new bike, if you can't see the holes, there is rim tape, and there is only really a need to replace it if you see and tears in the rim tape.

2) The weight difference isn't too much to be bothered about, especially commuting, just get the standard ones and save your money, being non ultra light, they will be thicker, and thus have slightly better puncture protection. if you want to protect against flats, I have to suggest a product called tire flats 2. It is basically a strip of flexy plastic you line your tires with. They do add a little bit of weight, but they guarantee against flats from glass, gravel or thorns (not potholes), and in my opinion well worth the extra bit of weight.

3)easiest way, more cost = better quality. Go for well known, such as continental, michelin, vittoria etc. I say look for ones with a bit of puncture resistance, and compounds which reduce rolling resistance. I can't speak for longevity (although I read good things), but a couple months back I switched to Continental GP4000S (with black chilli compound), and the tire flats 2. They replaced stock tires, and first time out I thought jeeze, I can feel the extra weight, but about 10 mins into the ride, I realised how much lower the rolling resistance was, and they grip for dear life around corners. Since changing, no flats whatsoever.

Wow long post sorry, but in summary:
-Go with stock tubes
-Tire flats 2 will be well worth it, especially if commuting
-My suggestion, Conti GP4000S. A bit of puncture protection, much lower rolling resistance, and they grip for dear life.

I'm of the theory that the thinner the tube, the more frequently you have to top off the air pressure.