Your requirements doesn't really narrow it down a lot, you basically want a perfect server or you're not really sure what you want.
For example,
Why apache with windows?
You know if you're gonna get a VPS or Dedicated, you're gonna have to pay for a windows license separately, which is around $10~20 / month, unless you go with shared host.
You can't install windows on Digital Ocean afaik, at least not on the 512MB RAM droplet. Plus you need AT LEAST a server with 1 GB RAM for windows.
Thing is, there is a difference between having 100K users in total, and 100K users hammering the server with concurrent requests. If you're expecting to have the 100K users using the app at the same time, then you're definitely going to need a dedicated server with a decent amount of RAM, probably even more than one depending on how heavy your scripts are.
Also, since you want apache, I'm guessing your site/scripts are written in php. You might wanna look for nginx webserver instead of apache if you're planing to have huge load.
Just out of curiosity, what will the job of the server side scripts be doing, are they only authenticating the user and doing basic stuff like small calculations and counts, or they are going to do huge calculations, image rendering or video encoding etc.. ? Because if you're planning on having a CPU intensive web application, you're gonna need a dedi, VPS or shared hosts will ban you if you abuse the CPU.
I'm not really sure how CPU intensive your application is, but if it's only normal database querying with some calculations and loops, my suggestion would be to start with a shared host, or a linux VPS with ~2 GB RAM, then once you feel the load on your server is increasing, you can get a dedicated or move to the cloud. By then you will be making enough money to be able to pay for the server.
KingOmar wrote m0ei And Hybrid :
That's a great solution as long as i don't need to withdraw money, but i urgently need a card that receives Money.
Someone correct me if I'm wrong, but as far as i know, it's not possible to receive money directly to your debit card/credit card in Lebanon, you can look for options like bank audi payment gateway or netCommerce on your site or some abroad bank account with an abroad credit card and a paypal account.
You can always receive money by bank wiring, or western union, but receiving money to your credit/debit card in lebanon, I would love to know how its done.