Ready to get started with NoSQL and MongoDB? Here are two 7-minute walkthroughs for installing MongoDB as a Windows service / OS X daemon.
These are both excerpts from my upcoming online MongoDB course for DevelopMentor. You can take the first 1 1/2 hours for free here:
Early access: MongoDB and NoSQL for .NET developers
Windows:
OS X:
Feedback welcome.
cheers
@mkennedy
Michael Kennedy on Technology 
…and for this series…
How can I start/install mongod.exe in my website with MVC Razor code?
Hi. You would setup MongoDB to start as a system service, just like you would SQL Server. It starts when you boot up and it stops when you turn off the server. From MVC, you just assume it’s running and talk to it.