Black borders around video output? Blender: 2.74

Window size: Default. 

Output: AVI Raw (tried other alternatives, and it gives the same result)

I'm having these issues with the rendering output of some animations i'm doing. 
A few days ago, this wasn't an issue at all. There were not borders or letter boxing look to the output of the video. But now all of a sudden there are. I looked at this persons question called "Full Video not Rendering" and they seemed to be having a similar problem but it's not answered and I tried the comment but it unfortunately didn't work either. 

For example

In a single rendered image it looks fine. No borders or anything. But when i render the animation, the output after all the frames have rendered, it looks like this:


And then if I put that file into another editing program (if needed), it ends up like this:


I feel like I may have pressed something but accident while working in Blender maybe causing this. I've seen something about the DispView and DispWin option, that sounded like it would work, but I can't seem to find them in the program.

Any one know how to fix this so its full screen without the black borders? 
Thanks!
Figured it out don't worry!

I don't know how or why it worked, but I basically just tested a sample animation a couple of times using the same format above but in different blender files until eventually, (and miraculously) the borders disappeared on their own. It seems my Blender was a bit buggy.  

However, I wouldn't recommend this if it doesn't work for an extended period of time, but mine luckily worked after 2 or 3 tries.