Is it possible to run Windows Server 2008 R2 on Amazon EC2

If your upload speed is generally pretty good, then it looks to be a slow upload to amazon, so using any sort of third party in the middle my help your speed, say uploading to and FTP site, then downloading from Amazon, which should be quicker than upload. Yes it involves an extra step, but it may make it quicker in the long run.

If your trying to upload Microsoft media, if you have an MSDN or Technet subscription maybe you could download it from there?

Your license fees are included in the hourly run-time charge from Amazon. It's a data center license, so you do not need to (nor are you ALLOWED to) install any license you may already own. As for terminal server/remote desktop service CALs, these can be purchased or installed. The server can be made part of your existing AD domain and contact your existing licensing server, or you can run it in workgroup mode and activate licensing service on the AWS EC2 server itself.

http://aws.amazon.com/ec2/faqs/#Can_I_use_my_existing_Windows_Server_license_with_EC2