ActiveX and Javascript aren't the same thing.
I'm not on my home system so I can't check but I assume that MS knows how to do it:
How to enable JavaScript in a web browser?
On the Tools menu, click Internet Options, and then click the Security tab.
Click the Internet zone (Earth symbol).
If you do not have to customize your Internet security settings, click Default Level. Then do step 4
If you have to customize your Internet security settings, follow these steps:
a. Click Custom Level.
b. In the Security Settings Internet Zone dialog box, click Enable for Active Scripting in the Scripting section.
The default on Windows 8 is to disable a lot of this type functionality because it can be exploited.
As others have mentioned already Java and Javascript have nothing to do with each other. Unless you
need to access a website that requires the Java browser plugin or you have some application that uses Java (pretty rare) I would recommend that you
not install Java. Note that I make my living writing Java code.
However if you want to install Java the general practice is to install 64-bit Java on 64-bit operating systems and 32 on 32 but you can always just install 32-bit on both as you are just really unlikely to need 64-bit Java.