I am total happy by using RADStudio Delphi, if that is too heavy, for learning into Object Oriented Programming I also can recommend to check out FreePascal with the Lazarus IDE.
Some of my apps are here on Forum available, there you can test and try to find out if they respond for your needs fast enough.
.Net/ActiveX/Com/Ole etc I try to avoid using, those probably lag a lot compared to native controls.