i am a windows user and c# programer im more comfortable with windows

Then your choice should be obvious. And don't fall into the "Linux is free, so Linux server will be free" trap. Especially if there are really two "M"s in your MMO the serverS will cost you much and the sooner you start thinking on multi server architecture the less pain you will have later.

I don't know about games, but for my day job I manage Windows servers and I've seen uptimes measured in years. Now, with reboots required from Windows Update that's hopefully going to be rare, but the point is: the whole "Windows crashes often" thing is utter nonsense on a well-managed box.

This.

Of course, use whatever you're more comfortable with. The slight difference in price between a windows and linux box won't be worth the hassle if you don't want to learn to love/live *nix.

If you're familiar with *nix servers, go for that, then.

I would recommend windows server, but I would hardly stress not using MSsql as database provider (I would recommend Firebird SQL as database server). Asp .Net is very reliabale and stable, unless you use custom native libraries in the active pages (that may impose danger to entire http server proccess if they are coded unprofessional IOP way).

I would hardly stress not using MSsql as database provider

Just out of curiosity, may I ask why is that?

I would hardly stress not using MSsql as database provider

Just out of curiosity, may I ask why is that?

If one does so (use mssql), I can tell with assumption neighbouring to certainity, that you will experience very very bad days , needing to dig out some super net kernel expert to log to your data again with some lucky proccess . There is a multitude of database authority proccesses access / loging, that are prone to any single change in OS or condition changes. It is the precious data in the end and, it is not worth it, unless you like adventures in the very critical systems.