Within one slide, let's say I have four lines, which I want to appear one by one, but only upon a click of the mouse. Right now animation let's me introduce them by clicking, but if I don't click it automatically introduces the line itself. How can I stop PPT from automatically introducing the next line in animation?

It must be a setting in the animation sequence. Do you have the entire 4 lines animated as one piece or have you animated each line individually?
You would need to make sure each line individually animated and ensure that each line has the Start option set to On Click.
If you have done the above already just upload a copy of the file, take out confidential content and I'm happy to take a look and give you feedback on how to fix.

Thanks a lot. I've attached one slide. I'm running Office 2011 for Mac.

You'll see that if you start the presentation and do nothing, each line pops in after about 8 seconds. In the attached, I did animation for each line separately.

Attached Files

test.pptx (52.0 KB, 8 views)

Ok I think I've found the problem..

In your Advance slide settings you have the After setting set to 00:23.90 so PPT is automatically doing the animations in order to meet this requirement. If you untick this option and run slide show mode, the animations do not appear until you physically click the mouse.

Thanks a lot. This sounds really promising, but where is the advanced option? I've looked high and low! Screenshot attached, if it helps.

Attached Images

Screen Shot 2014-09-26 at 10.11.12 PM.png (135.1 KB, 14 views)

It should be in the Transitions tab.
Sorry I'm using PC and don't have a MAC to check and see.
I've attached screenshot.

Attached Images

screenshot.3jpg.jpg (74.7 KB, 13 views)

Thank you! Thank you! Thank you!