Are you using one of our pre-compiled packages or a build you made yourself from source code?
If you are compiling it yourself, make sure you compile it in release mode and set <compilation debug="false" in Web.config because a debug build will be much slower.
The mojoPortal log is under Administration > System Log but on a machine like that I don't think it will be a problem of lack of resources. However if you are running the site over the internet from home using a consumer internet connection it may not be a very fast connection.
See also
Using the AppKeepalive To Speed Up a Low Traffic Site
Visual Studio Performance Advice
Hope that helps,
Joe