Sorry, I'm really not savvy enough to do this.
Do I type these commands in to the terminal?

drwx------ 20 userx users 4096 Oct 13 12:13 .config
drwxr-xr-x 5 userx users 4096 Oct 8 06:51 .fluxbox
drwxr-xr-x 3 userx users 4096 Oct 13 15:27 .fvwm
drwxr-xr-x 9 userx users 4096 Oct 13 15:28 .fvwm-crystal
drwxr-xr-x 6 userx users 4096 Oct 9 18:23 .gkrellm2
drwxr-xr-x 5 userx users 4096 Oct 9 16:57 GNUstep

they are not commands, but s display of what your hidden directories look like,so you will know them when you see them, and they will not be the same, only they have a dot in front of the name, making them a hidden file, and yes, taken from the terminal.
just look for one that has the name of your desktop, that is what you need to find, then change the name, logout, login. to get a new one. Keeping i mine this is a shot in the dark attempt to reset your confi files to see if that will get your menu back. you could even open that directory and look for a file with the word menu in it then rename that one and do the same.

Hi,
This is what I got; I don't know what the "name of my desktop" means; can you see if it is listed here? Also, how would I change the name?
You mention "opening that directory"; which directory? Do you mean the name of my desktop? Sorry, I really don't understand most of what you are suggesting. Just not educated enough on computers/linux. I have to be walked through every step, told what to type in the terminal, etc. Sorry.
Here it is:

paul@FOSS ~ $ ls -la
total 232
drwxr-xr-x 24 paul paul 4096 Oct 15 08:04 .
drwxr-xr-x 3 root root 4096 Aug 13 19:33 ..
-rw------- 1 paul paul 1735 Oct 13 23:10 .bash_history
-rw-r--r-- 1 paul paul 220 Aug 13 19:33 .bash_logout
-rw-r--r-- 1 paul paul 4000 Aug 13 19:33 .bashrc
drwxr-xr-x 15 paul paul 4096 Oct 9 11:05 .cache
drwxrwxr-x 3 paul paul 4096 Oct 2 11:18 Calibre Library
drwxr-xr-x 22 paul paul 4096 Oct 13 08:25 .config
drwx------ 3 paul paul 4096 Aug 13 19:34 .dbus
drwxr-xr-x 2 paul paul 4096 Oct 14 21:35 Desktop
-rw-r--r-- 1 paul paul 45 Oct 12 16:41 .dmrc
drwxr-xr-x 3 paul paul 69632 Oct 14 12:08 Documents
drwxr-xr-x 4 paul paul 4096 Oct 10 23:15 Downloads
drwx------ 4 paul paul 4096 Oct 12 16:01 .gconf
-rw-r----- 1 paul paul 0 Oct 3 17:15 .gksu.lock
drwxr-xr-x 3 paul paul 4096 Oct 12 19:44 .hplip
-rw------- 1 paul paul 27420 Oct 15 08:04 .ICEauthority
drwxrwxr-x 2 paul paul 4096 Aug 13 19:34 .icons
drwxrwxr-x 4 paul paul 4096 Aug 13 19:34 .linuxmint
drwx------ 3 paul paul 4096 Aug 13 19:34 .local
drwxr-xr-x 5 paul paul 4096 Aug 13 19:45 .mozilla
drwxr-xr-x 2 paul paul 4096 Aug 13 19:34 Music
-rw-r--r-- 1 paul paul 262 Oct 12 16:41 .pam_environment
drwxr-xr-x 2 paul paul 4096 Aug 13 19:34 Pictures
-rw-r--r-- 1 paul paul 655 Aug 13 19:33 .profile
drwxr-xr-x 2 paul paul 4096 Aug 13 19:34 Public
drwxrwxr-x 2 paul paul 4096 Oct 10 10:37 .pypar2
-rw-r--r-- 1 paul paul 0 Aug 13 20:44 .sudo_as_admin_successful
drwxr-xr-x 2 paul paul 4096 Aug 13 19:34 Templates
drwxrwxr-x 2 paul paul 4096 Aug 13 19:34 .themes
drwx------ 4 paul paul 4096 Oct 5 11:53 .thunderbird
-rw-rw-r-- 1 paul paul 0 Aug 14 09:32 troubleshoot-logs.txt
drwxr-xr-x 2 paul paul 4096 Aug 13 19:34 Videos
drwxrwxr-x 2 paul paul 4096 Oct 8 13:28 .winff
-rw------- 1 paul paul 49 Oct 15 08:04 .Xauthority
-rw-rw-r-- 1 paul paul 131 Oct 12 16:40 .xinputrc
-rw------- 1 paul paul 1626 Oct 15 08:30 .xsession-errors
-rw------- 1 paul paul 3489 Oct 14 22:57 .xsession-errors.old
paul@FOSS ~ $

which one did you download? If you didn't get a community edition
I see your linuxmint dir there, that could be the one, but you still need to look in your .config directory to see what is in there. xfce4 config gets put inside there, and I am not sure about the other two. This too will help familiarize yourself with what it kept within your home.

I downloaded Mate 64 bit - it's Linux 18.3
Sorry, I know you are trying to help, but this is so far over my head, I don't understand any of that last sentence, or how to go proceed with this information.
["I see your linuxmint dir there, that could be the one, but you still need to look in your .config directory to see what is in there. xfce4 config gets put inside there, and I am not sure about the other two. This too will help familiarize yourself with what it kept within your home."]
All the programs still work, such as VLC, Deluge, Libreoffice, etc. So, the programs are all still there and functioning. In fact, when I click on "menu", all the other icons work, under the "places" and "system" headings. Just nothing works under "applications". If there is no way to make what you say understandable to a total newbie like me, no problem. I don't want you to waste your time. I do appreciate you trying to help though.
Thanks!

I just got done installing Mint cinnamon (again on one of my partitions, I like this desktop anyways) that is where cinnamon has its desktop files in that bolded one. as I did not see that in your output you might just have xfce4 then, or MATE desktop.

in a terminal
to see its contents. look for xfce4 or mate . keep in mind this is just a shot in the dark on fixing your menus that got screwed up somehow.

This is what I got when I typed in that command; don't know if it helps at all?

total 112
drwxr-xr-x 22 paul paul 4096 Oct 13 08:25 .
drwxr-xr-x 24 paul paul 4096 Oct 15 17:18 ..
drwx------ 2 paul paul 4096 Oct 12 16:39 autostart
drwxr-xr-x 3 paul paul 4096 Oct 15 17:19 caja
drwx------ 6 paul paul 4096 Oct 2 11:16 calibre
drwxrwxr-x 2 paul paul 4096 Oct 15 19:04 dconf
drwx------ 6 paul paul 4096 Oct 2 08:22 deluge
drwx------ 2 paul paul 4096 Oct 14 19:27 gtk-2.0
drwx------ 2 paul paul 4096 Oct 15 17:18 gtk-3.0
drwxr-xr-x 2 paul paul 4096 Aug 13 19:33 hexchat
drwxrwxr-x 3 paul paul 4096 Aug 14 09:03 libreoffice
drwxr-xr-x 3 paul paul 4096 Sep 19 22:59 mate-session
drwxrwxr-x 3 paul paul 4096 Aug 13 19:34 menus
-rw-rw-r-- 1 paul paul 2402 Oct 13 08:25 mimeapps.list
drwxrwxr-x 2 paul paul 4096 Oct 9 06:58 mintmenu
drwxr-xr-x 2 root root 4096 Oct 7 18:05 nautilus
drwx------ 2 paul paul 4096 Aug 13 19:34 pulse
drwxrwxr-x 2 paul paul 4096 Oct 2 13:37 solaar
-rw-r--r-- 1 paul paul 9269 Aug 14 10:06 Trolltech.conf
-rw------- 1 paul paul 632 Aug 13 19:34 user-dirs.dirs
-rw-rw-r-- 1 paul paul 5 Aug 13 19:34 user-dirs.locale
drwxrwxr-x 2 paul paul 4096 Oct 14 22:56 vlc
drwx------ 2 paul paul 4096 Aug 13 19:41 xplayer
drwx------ 2 paul paul 4096 Oct 7 17:10 xreader
drwx------ 2 paul paul 4096 Oct 14 12:08 xviewer
drwxrwxr-x 2 paul paul 4096 Oct 1 22:40 yelp
paul@FOSS ~

drwxrwxr-x 2 paul paul 4096 Oct 9 06:58 mintmenu what is that one?

now I'm wondering just hat mint did you install?
this is the one I have installed, cinnamon flavor
https://linuxmint.com/download.php

mod:
yours
you might have MATE installed.
do you know how to create a directory? if yes, create a temporary directory and move them into it. logout then back in again and see what happens. if you get stuck switch tty's login and navigate to that temp dir then move them back to the original place then try logging again, may require just rebooting to get a new login.