I did a fresh install of Ubuntu 18.4 LTS, coming from Windows, and everything was working great! I installed my needed apps; I'll list them below in case they have something to do with the problem, and the system did an update. I rebooted and now the terminal is refusing to run. If I try and open it, all that happens is that it tries to load but stops after about 5 seconds or so. I've downloaded xterm so that I could use terminal commands again, but this has caused problems with updates & installs as well.
I'd sincerely appreciate any help, I cannot seem to figure out what's wrong and I really don't want to have to reinstall the OS.