Several things are happening that will make things that use to work no longer work. They involve the closing of security exploits. When you install IE7, and when you install Windows security updates, certain changes are made, to both settings and software, to improve security. For example, "safe for scripting" scriptlets are a major source of virus propagation (so they're not very safe, eh?) so in a future security update to the operating system, the capability will be "killbit"-ed -- the operating system code that allows for scriptlets in browsers will be overwritten with code that specifically ensures that scriptlets cannot run.
So the key for you is to determine what is the actual problem, determine whether it is because of a setting change or due to something being permanently disabled, and in the case of the former, how to switch the setting back.
ActiveX is controlled through the security settings of Internet Explorer Options. Tools / Options / Security / Custom level... / ActiveX Controls and pug-ins.