Custom Windows AMI for Amazon EC2

I am new to the Amazon EC2 services and I am planning to host a Windows based vm on Amazon. I have lot of fuzziness about AMIs on Amazon. So my first question would be, am I be able to install softwares and frameworks(e.g. Silverlight, .NET, etc) on a existing Windows instance that I select? And if not, how can I create a custom AMI so that I can install these softwares that I need before I submit it to Amamzon and launch?

Thanks a lot for your help :)

Deeply appriciated

You can install pretty much any software on an Amazon AMI that you would ordinarily be able to install on a virtual server and use via remote desktop (no World of Warcraft, but Silverlight, .NET, your custom software etc. can all be installed). Be sure to respect licensing terms.

You can then burn a custom AMI from that Amazon baseline plus your own installation so that you can easily fire up instances with exactly what you need already installed. (Again be careful of licensing terms).