Problem after rendering a file

I want to ask you a couple of questions. Is the 2-minute animation all one continuous shot? What is the frame size and frame rate? 

If the comp is not one shot, you should consider making each shot a separate comp. That is how Pixar, Disney, and every other animation studio I know of works on their projects. Create a shot, render it, create more shots, render them, then edit the final movie in an NLE using the shots you edited. You'll get a better job in the long run and save time.

Even if the 2-minute comp is a single shot, there is a way to break it into smaller segments and stitch them together later. AE is not an editing app. It is designed to create shots (animation, motion graphics, and visual effects).

As a quick test, set your work area to the first 10 seconds of your project, add it to the Render Queue or the Media Encoder and choose to render only the work area. Use one of the standard presets in the Media Encoder, like YouTube HD or the Best Quality default Output Module preset in the Render Queue. If the render is fine, then select all the layers in the comp, press the U key twice to reveal all modified properties, and start looking for things that could foul up resources or drain the memory, like particle systems, grow bounds, or anything else that you might turn off or reset. 

If you are still lost, we need embedded screenshots (by dragging or copy-and-paste to the webform) instead of attached ones. Screenshots should show us the whole UI and the modified properties of the layers or the modified properties for your render settings. 

I've been using AE since AE was a baby, and more than 90% of my comps are less than 7 seconds because the average time between cuts in a movie is less than 7 seconds. Some of my comps have dozens of nested comps and hundreds of layers, and some take several minutes a frame to render. When I suspect that I am pushing my system to its limit, I always render image sequences so if I get a failure on frame #27, I can look at what is happening in frame 27, fix the problem, and then pick up the render there—no wasted render time with image sequences. 

I hope this helps.