A while back I recall attempting to install an updated version of Ruby on my Mac. I had an interest in the language and thought I would give it a go. I followed detailed instructions that lead me through installing macports so I could have access to bash commands. Well, now every time I open up my terminal to use it, it defaults to cat. If I Control + D out, I go into bash, again, and I end up in ruby, once more and I end up in top where it dead-ends. I tried changing my terminals default path to usr/bin/login but after I log in it defaults again to cat no matter what I do. If I force close the processes through the GUI they just reopen. I am at quite the loss here and any help would be appreciated.
I'd try opening a terminal as another user. Assuming that works, check the .profile file (its .bashrc for most other *nixes) for the original user, and remove any mention of cat there
You can use Terminal > Shell > New Command to run a shell without reading the profile or rc files. In the dialog that appears, enter the following command:
Then you can use an editor to examine your shell customizations to address the problem.