Thanks guys this was all pretty helpful I appreciate it...so matching your tippet with the size fly your using will give you the best presentation?
It's about balance, there's trade-offs each way. Generally finer tippets will produce less drag nomatter what. They also cut through water easier, enabling you to get deeper with nymphs. However, they obviously break easier. In order to prevent that, you have to fight fish longer, often too long. You lose more flies to snags. And they don't turn over as well, leading to difficult casting, less accuracy, and often have problems with twisting and knotting.
With larger flies, it's just that you need more stiffness to turn them over properly, and it's easier to control drag. Hence, larger tippets. With tiny flies, a stiff leader will induce too much drag, and they're easy to turn over anyway, hence, smaller tippet.
For a beginner, a tapered mono leader is fine. I'd get a 9 ft, 4X. Snip back about two feet and replace with the tippet size of your choice. Going with 4x simply allows you to get a little larger. If you have a 5x leader and snip back to use 4x or 3x, you might not snip back far enough and the likelihood of losing the whole tippet goes up.
Personally, my preference in leaders, when compared to tapered mono store brands, is a stiffer leader and a softer tippet. When you get more advanced and understand what you really want in a leader, then you can buy leader tying kits for about $40 which will last you a decade or more. You'd have to buy more tippet of course, but the main leader you can make softer or stiffer, longer or shorter, etc., for various situations.
Tippet materials vary in stiffness. Stiffer acts a little more like a bigger tippet, softer acts like a thinner one. Fluoro is stiff in comparison to to the copolymers out there (commonly called mono). There's less stretch and it is more abrasion resistant, often a good choice for nymphing. IMO, mono's are better for dry flies. But you can indeed use either for either. I tend to like the softest mono's I can find. Rio Powerflex is my standby, though I use Rio Suppleflex when I can find it.