When I visit your site it does take a long time for the first view of each page but after clicking around it seems much faster. This is a fairly common issue in ASP.NET because of the JIT compilation that occurs when an application first comes to life (ie on the first request). You can see one thread about it here, or google for "asp.net slow, jit compilation". Yours does seem rather longer than it should but to me that is fairly common at cheaper hosting.
If your site does not get much traffic this problem seems even worse because what happens is if your site goes 20 minutes with no traffic IIS shuts down the application so then you do get another visitor and the JIT has to happen again because the application was previously shut down so the few visitors you get all experience a slow site. In mojoPortal we have an experimental feature that you can try that may help mitigate this a little. If you look in Web.confiig for this setting and change it from false to true.
<add key="UseAppKeepAlive" value="false" />
Then after the first requests when the application wakes up and does its JIT compiling, then a background thread will be launced that will make a page request to the site every 15 minutes in order to make sure there is enough traffic to keep the application awake.
If this problem is at all related to MySql, the only issue I could think of is if it has slow name resolution fromthe web server to the MySql server, which would be a hosting issue. There is nothing intrinsicly slower about MySql. This site, mojoportal.com is running on MySql and it has good performance.
So, in summary I think part of the problem is JIT compilation but there may be hosting factors involved as well.
Hope it helps,