When you first start the IDE, it asks you to select a user profile via a dialogue.  I usually find myself gravitating towards "C#" or "General"  profile, but sometimes I pick a different profile and don't quite find what I'm looking for because the profiles determine what features you see in the File menu toolbar.  In my specific case, the "Tester" profile didn't include the Performance Tools options under Tools.  The problem for me is that the IDE doesn't make it clear how to get the profile back to normal. 

The way I do know how to undo the user profile selection and set it to C# (in this example) is to open up the Visual Studio Command Prompt, navigate to \Common7\IDE\Profiles under the install path, and then invoke devenv.exe from the command line as follows:  devenv /resetsettings csharp.vssettings

There are other settings files there you can substitute in for csharp.vssettings based on the user profile you want to use - the IDE then opens with that new user profile settings.