It's good for a question on SE to be focused. However, there is a broader context here, which is that you want your activities to be (a) safe and (b) comfortable and enjoyable, so that you'll want to continue doing winter mountaineering rather than letting your crampons gather dust in a closet. In this context, the exact choice of crampons is a relatively minor issue. More important issues are getting good self-arrest training, practicing self-arrest often enough so that you're likely to succeed in real conditions, getting boots that are comfortable, and figuring out clothing layers that keep you comfortable.
So anyway, in the terminology used in the question (which I think is probably UK-specific or European?), the standard setup is a pair of 12-point C2 crampons such as Grivel G-12's, which are what I own. This is a versatile setup that will also work on low-angle terrain or on higher-angle ice. Any other setup is extremely specialized and is not really what you want as the only pair you own. Most people who own this type of setup never feel the need to buy any other type of crampons. Because crampons and crampon-compatible boots are expensive, it doesn't really make sense to buy more than one setup unless you get into something really specialized, like ice sport climbing. There is no real concept of buying starter crampons or buying a "first crampon grade."
If I'm understanding correctly what C1 refers to, then those things suck. I've seen people using them, and they're horrible. The crampons keep falling off the boots.
For boots, you probably want the most comfortable lightweight goretex boot you can possibly find that is compatible with your C2 bindings -- I guess this would fall in the B2 category. It's true that, e.g., double plastic boots will keep your feet warmer and drier on a long trip at high altitude -- but they will also probably cover your feet with blisters and make you miserable, and the extra weight will make you extremely inefficient. If you get started with winter mountaineering, enjoy it, and eventually start to feel that you're expending too much physical effort front-pointing, or if you want to go to altitudes above about 5000 m, then it might be time to think about getting a stiffer pair of boots (B3) or boots with more insulation.
Besides ice ax and crampons, the other thing I find really helpful is a pair of microspikes, which are a brand of rubber elastic booties with little crampon-like spikes built in. You can put them over any shoes or boots. They're compact and lightweight, and they're extremely helpful for conditions where you have to walk across some mixture of snow, ice, dirt, and rocks (conditions where crampons would be a total pain at best). Depending on conditions, my setup may consist of ice ax+crampons, ice ax+microspikes, or ice ax+crampons+microspikes (or any of the above along with snowshoes).
While you're out buying crampons, don't forget to stop at a hardware store and buy an appropriate file, and learn how to sharpen them.