If I have the effects (ie. colour correction) setup just the way I want them on one event, is there a way to copy or apply those effects onto another event without redoing it from scratch?
Right click in the clip where the CC is and select Copy
Then goto where you want to apply the CC
Right click and select Paste Event Attributes.
It will only work this way if all you have done is COLOR CORRECTION and no other stuff; if you have done other stuff, everything will be transferred over.
You can always create FX Presets when you create an FX you like for later use.
That's the way I do it. If there's a better way, I don't know of it, but I'm always surprised at what Vegas can do so there may be other ways. Either make a preset (as Jubal28 says) or Paste Event Attributes (like John said).
To disable or delete? Just click on the effects square (green) -- it will list ALL of the effects in check boxes at the top of the effects window. You can remove the checkmarks (to disable), or you can right-click and select "remove" on the menu.