My experience with MySql and .NET (and this has been a while - years) has been poor simply because the ADO.NET stuff for MySql was poor (and I have no idea if it's changed).

I was under the impression that Amazon's cloud required the client image to be linux?

Frankly, for smaller sites, you can get shared hosting for $10 a month that might be sufficient (and you can grow to a $50/month slice and then a $300 a month dedicated then to $$k for many dedicated). All prices are from Webhost4Life.

Since running a single EC2 instance = $70 a month if left up full time, I think there are vastly cheaper options out there.