If you want the tree menu to be in a frameset, you can use the Frameset tab to design and write your frameset file.
If you are not using framesets, you can completely ignore the Frameset tab.
Check the "Tree menu is in a frameset" option if you are using framesets. The main effect of this button is that when a user clicks on a link, by default that link will be loaded into a frame with the name "emtcf" (eMenuTree content frame). If this frame does not exist, the link will be loaded into a new window. (The javascript code looks for the frame "parent.emtcf".)
All the frameset options are provided for your convenience. They do not affect the tree menu script. They are only used when writing the frameset file "eframeset.htm". You write this file by using "Write frameset" command on the Run / Tools menu or the "Write eframeset.htm" button.
You may change the name of eframeset.htm. If you want it to be your default page, you can change its name to "default.htm". If you do this, you may want to use the "File / URL to preview" option to tell eMenuTree to preview this file.
The file which you load into the tree menu frame should contain your tree menu (i.e. it should have a link to emenu.js). If you leave the "File / URL to load into the tree menu frame" option blank, eMenuTree will load ehomepage.htm into the tree menu frame.
You can put as many frames and framesets as you want in your frameset file. For example, you can put a small frame over or under your tree menu frame. The only rule is that links will be loaded into the frame with the name "emtcf".