I'm missing buttons and pull down menus in Mail
I'm going to assume you're talking about Mail on a Mac.

Since you haven't included a screenshot of the actual window you're talking about, I'll refer you to the fact that you can customise the toolbars in various windows within Mail.

To do this: go to View > Customize Toolbar... 

This menu option relates to whatever window type you have active at the time. 

For example, if you've got a New Message window active (commandN) and then go to View > Customize Toolbar... you'll be able to customise the toolbar within the New Message window.

Likewise, if you have the Viewer Window active (i.e. the main default window that Mail launches with) and then go to View > Customize Toolbar... you'll be able to customise that toolbar.