where can I find the height settings on the HTML page?
The easiest way is to use either the F12 Developer Tools in IE or the Firebug addon in Firefox.
Look in the body section then drill sown into that section by clicking on the '+" signs until you reach a table with the class of ",stctb". The right hand side of the window will let you look for the attributes of the table; height is one of them. If you compare the two you will see one is 14px. the other is 24px.
This is a style that is derived and applied from the supporting JS files.
I would suggest that instead of copying and pasting the menu code into each page you look at the help section about Creating a JS Include File and use that strategy. That way you can make changes to your navigation and publish one file that is used for all your pages. Use the Web Path option (click Resource Folder in the Global Settings and then click on the Folder icon at the right in the bottom box to select between Resource Folder and Web Path).