Well, I'm not a total computer expert, but maybe I can come up with something.
Is there anything you did shortly before the computer started displaying odd error messages, which might have caused the issue? Maybe you deleted or moved a file or folder, downloaded a new program, recently updated something?
I have no idea what that DLL file might be, or what program it belongs to. If the error comes up again, perhaps write it down so you're certain of what the name is. That might help when you're looking it up.
A DLL file is important in running programs, though, so if you're missing an important DLL file, that might help to explain the issues you're having. ( https://support.microsoft.com/en-us/kb/87934)
Concentrating on the werfault.exe error, some possible solutions I've found are updating or reinstalling drivers. A few people have suggested turning off Windows Error Reporting, and seeing if they still get the same errors after doing so. Another possibility is that your computer may be infected with some sort of malware.( Error code: WerFault.exe - Application error - Microsoft Community
Open up Windows Task Manager (Ctrl+Shift+Esc) and see what your computer is running. Are there any programs taking up a lot of RAM or processor speed, processes that you don't recognize or that look strange, or just an insane amount of processes running?
Also try running malware scans. Sometimes one program will detect things another didn't, so consider running multiple scans. Some free programs include Windows Defender, Microsoft Security Essentials, AdwCleaner, MalwareBytes, and ESET Scanner. Don't run multiple programs at once, though, as they can sometimes conflict with each other if you run them simultaneously.