Android - Can you get a list of the RUNNING applications on Android for the purpose of activating them?

Sounds like you're overthinking it. Android goes out of it's way to intelligently manage applications and resources. When you leave an app it will generally keep running as long as the resources are available. Long pressing Home and selecting it or just launching the shortcut again should take you right back to the running app.

Theoretically it shouldn't matter if it is still running or not, though -- every app is supposed to save it's state in such a way that if the OS kills it before you come back, it should still be able to launch back to the same state you left it in. This isn't universally applied in programs yet, but it does seem to be much more widespread these days -- presumably because the developers are getting used to the "android way."

The app Smart Taskbar will show you a list of the all tasks(apps) that are currently running on your device and allow you to switch to that app, similar to the native functionality but you are not limited to the 6 most recent apps.

Basically it opens from any screen and also lets you set some shortcuts and widgets and choose from all installed apps (like the app drawer) so you can complete any task from anywhere on your phone without having to go to the home screen first.

There are a bunch of other apps that let you switch between running apps, just search the market for "task switcher."