Is it possible to create and use menus in (terminal-based) vim?

Yes, it is possible. You can load menu.vim (the default gvim menu definitions), or you can just start from scratch and create your own, then access them through :emenu. This doesn't give you nano-like always-visible menus, though; it gives you the ability to navigate menus using command-line tab completion.

If the user doesn't have a vimrc, you'll want to start by disabling vi compatibility:

:set nocompatible

Enable smart command line completion on <Tab> (enable listing all possible choices, and navigating the results with <Up>, <Down>, <Left>, <Right>, and <Enter>):

:set wildmenu

Make repeated presses cycle between all matching choices:

:set wildmode=full

Load the default menus (this would happen automatically in gvim, but not in terminal vim):

:source $VIMRUNTIME/menu.vim

After those four commands, you can manually trigger menu completion by invoking tab completion on the :emenu command, by doing :emenu<space><tab>

You can navigate the results using the tab key and the arrow keys, and the enter key (it both expands submenus and selects items). You can then make that more convenient by going a step further, and binding a mapping to pop up the menu without having to type :emenu every time:

Make Ctrl-Z in a mapping act like pressing <Tab> interactively on the command line:

:set wildcharm=<C-Z>

And make a binding that automatically invokes :emenu completion for you:

:map <F4> :emenu <C-Z>

I've had the problem myself that I can't remember all the commands and key combinations for plugins I am using. Plus, I wanted to have simple ways to quickly execute commands without having to set new key mappings or inventing commands to access them.

Vim-Venu

I've written a small vim menu plugin that allows you to define menus for each filetype that you might edit with vim. This way, you can define the menu option 'Compile' for different filetypes and initiate the correct instructions to compile the code depending on what file you are editing (.py, .c, .c++, ...). Or create a submenu for 'Table' plugin commands in a markdown file.

Check it out here: https://github.com/Timoses/vim-venu

As a side note: I think everybody should choose their own favorite text editor. Vim does have a little barrier (which is worth learning!). If somebody is not willing to learn, then vim won't be of much use for that person.