MP3 Diags
You may want to look at the change log here, especially if you installed an older version before.
While the development for 1.0 is frozen, I'll fix any serious bugs that are found and reported, provided that I can reproduce them or at least have a good idea about what might be causing them. Less serious bugs and feature changes are addressed in 1.1. I am aware of several outstanding bugs, which I can't fix due to lack of user feedback: I can't reproduce the bug and I can't make a reasonable guess as to what's causing it, so I need more details from the reporter, but the reporter doesn't provide those details. After a while these bugs will be closed. My plan is to fix bugs in 1.1 in a timely manner, so potential bugs shouldn't be a big issue (at least if you keep backup copies of your MP3s). Note, though that usually bug fixing requires user cooperation, so it's not only up to me to make a fix.
From time to time you may want to check the MP3 Diags blog, where announcements about new versions are made, both about bug fixes for the current stable release and about the release under development (i.e. 1.1.) Then you can decide based on what changed in a given version if you want to upgrade or not. (If you use an RSS reader, you can add that page to it, so you see the notifications automatically.)
There are both source files and binaries, for several Linux platforms, as well as for 32bit Windows. More details can be found at the main MP3 Diags download page.
Uninstallation
How the uninstallation should proceed depends on how the program was installed. If you installed from sources with Install.sh, there is an Uninstall.sh. If you installed on Windows using the installer, you can use both the Control panel and the "Uninstall" entry created when MP3 Diags was installed. If you used a package manager on Linux, use the same thing. If you just copied binaries, remove the binaries.
Keep in mind that besides the executable, there are data files and settings. You probably created some data files, and if you are sure you no longer need them you should remove them manually. Note that the data files come in pairs. Although you only specify an ".ini" file when you start the program for the first time (or when you create a new session), two files get created. The ".ini" only stores settings, while the actual data is stored in a file in the same directory and with the same name but with the extension ".dat".
Besides the ".ini" and ".dat" files, there is a small configuration file which is named ~/.config/Ciobi/Mp3DiagsQQQBRANCH_DQQQ.conf on Linux and similar systems. That file should be removed as well if you want no trace of MP3 Diags left on your computer. (Of course, you lose your settings, should you want to reinstall MP3 Diags.) The corresponding place on Windows is the registry entry HKEY_CURRENT_USER\Software\Ciobi\Mp3DiagsQQQBRANCH_DQQQ.
If you used shell integration, you should disable it before simply removing the program, so it won't leave garbage in your system. This is done automatically by the Windows uninstaller. You can do this manually by running the program with the "-u" parameter or by going to the Shell integration configuration page and unchecking all the options there.