Because it's not a bad question. You're getting answers from a lot of people who are either so buried in the deeply technical side of things or locked into the past that they don't really understand it. Having shepherded a couple of dreamy startups through this phase, though, I don't think you are either crazy or necessarily under-qualified to make a successful site. To be honest, it no longer takes the hardcore technical skills that it once did, if in fact it ever did. Technical competency is over-rated by technical people; there are super-successful web businesses out there that started out (and sometimes even continued) with really shoddy coding and infrastructure setup. Craigslist and PlentyOfFish come to mind as examples. I know several others without such name recognition but which nonetheless did quite well for their owners, who slipped along with very basic programming skills and almost no hardware competency whatsoever.
Having the ability to outsource your infrastructure makes it even easier to do this today. I'm going to stay away from the "C" word because it's so shot through with marketing dross and misunderstanding now. But it's entirely possible to effectively do away with almost all the Windows admin if that's not your strength by going with hosted services. You are probably a long, long way from having to worry about Windows/LAMP stack comparisons even at your stated traffic goals, and using a hosted service will abstract that to the point where you aren't going to need to worry about it anyway. I wish you the best, but the reality is also that few sites make it big anyway, so while scalability is certainly something to consider at this stage, you shouldn't allow it to hobble your choices excessively. If you actually get there, it's almost certain you are going to have both the resources and the need to rip everything up and re-do the entire site from scratch once or twice along the way anyhow. You can re-tool then if you must.
Abstracting hardware doesn't absolve you from making other design choices that will afford scalability, and you should have some understanding of what's going on under the hood so you can make those appropriately. But you don't need all that to get started. I don't know anyone, at any skill level, who actually correctly made all the right choices on their first pass. You'll be learning along the way. That's actually an advantage; tech is filled with people who found their comfort levels and can't adjust to newer models.
It sounds like you are asking as much about your dev environment as production. I would say "yes," move it all to a hosted environment. At this stage, you don't need to be worrying about the underlying nuts and bolts. Get up and running quickly and easily. Be flexible and make adjustments along the way. You probably don't even need to go with a full-on PaaS provider right now, either; get a cheap hosting plan with a company that will help you scale when you need to. Depending on your service requirements, you can go with best of breed hosting to find the most efficient solutions for your various problems... use a SaaS vendor for version control, use a CDN for content hosting, and so on. It's cheap, it's fast, and it reduces the time and cost of failure. Failure is undoubtedly something you will run into a few times along the way. That's going to happen whether you are a technical genius or just some schmoe with a good idea. Build it in to your plans; don't over-invest (whether in time or money) in things until you can see better how things are working out.
If you have a good idea, don't be too afraid if you don't know what you are doing. A lot of the best people don't. One of the most valuable lessons you can learn is what not to spend time on, and a lot of things that certain folks here on Slashdot hold dear are things that you don't necessarily need to spend a lot of time on right now. Prove your concepts first. If you turn into the next Facebook, you can worry about infrastructure then. Until then, don't let the idea that you need a Facebook-worthy infrastructure before getting started to hold you back. Re-format that VM server into a games machine and go rent time elsewhere.