Removing or Uninstalling Ruby, Rails, and/or Gems from Mac OS X 10.9.4

Question

I had some health issues and was away from my iMac for about 6-8 months. I’m not exactly sure which version of OS X was running when I stopped using it, but I had just installed Rails and was about to begin a tutorial. When I was finally feeling better and got back to work, I had like five OS updates, including the Mavericks package, so I updated everything and am currently running Mac OS X 10.9.4.

I also noticed that my version of Ruby and/or Rails was not current, so I updated that to 1.9.3, I think. Anyway, I received some errors on the install during my terminal session, and it appears to be somewhat of a mess. Here is an excerpt of my terminal session as it was trying to update Rails and Gems:

Downloading https://github.com/wayneeseguin/rvm/archive/stable.tar.gz

Upgrading the RVM installation in /usr/local/rvm/
chmod: Unable to change file mode on /usr/local/rvm/scripts/aliases: Operation not permitted
chmod: Unable to change file mode on /usr/local/rvm/scripts/fix-permissions: Operation not permitted
chmod: Unable to change file mode on /usr/local/rvm/scripts/functions/db: Operation not permitted
chmod: Unable to change file mode on /usr/local/rvm/scripts/functions/manage/ree: Operation not permitted
chmod: Unable to change file mode on /usr/local/rvm/scripts/functions/utility: Operation not permitted
chmod: Unable to change file mode on /usr/local/rvm/scripts/irbrc: Operation not permitted”

Here is another error message:

Installing required package: gdbm.........
Error running 'requirements_smf_lib_install gdbm',
showing last 15 lines of /usr/local/rvm/log/1404517181_ruby-2.1.2/package_install_gdbm.log
++ printf %b 'There were package installation errors with SM Framework, make sure to read the log.

My question for some Ruby on Rails expert who is familiar with the latest Mac OS X is:

Is there a way to remove all the Rails and gems and all the extraneous code or software, so I can just be left with the Ruby that is included in the Mac OS X, in order to have a clean slate to start over? Or, would it be best to just remove all things related to and including Ruby, Rails, and Gems, so I can re-install everything fresh and clean to my iMac?

I am very new to both Ruby and Ruby on Rails but I would really like to go through a few tutorials and learn them as best as I can. Any advice or help would be greatly appreciated, as I have searched quite a bit and not really found a great answer.