@philmiller278 No problem. I'm not entirely new to Linux, but when it comes to RPi or RetroPie I'm a "freshman". From my tries and errors, I came up with the following summarized procedure to get RetroPie up and running, so it might come in handy to you and others:
Download the latest RetroPie pre-built image;
Extract it using WinRAR, 7-Zip, etc.
Write the extracted image file using Win32 Disk Imager (on Windows) to the SD card;
Boot RetroPie and configure your controller;
In the RetroPie configuration menu select "raspi-config" or press F4 and type "sudo raspi-config";
Select "Expand filesystem" and reboot when prompt or type "sudo reboot";
Once restarted, update your system packages by pressing F4 and then typing "sudo apt-get update", and once completed "sudo apt-get upgrade", replying with "y" pressing Enter;
Reboot ("sudo reboot");
F4 again and type "sudo ~/RetroPie-Setup/retropie_setup.sh";
Update RetroPie-Setup script;
Update all installed packages (kernel too if you want);
Perform reboot;
F4 again and type "sudo nano /boot/config.txt"
Uncomment (remove "#") lines "hdmi_force_hotplug=1" - this solved my issue of not having image at first boot after power cycling; and "hdmi_drive=2" - this solves the issue of not having sound over HDMI;
Exit and save by pressing "Ctrl+X", press "y" and type Enter to overwrite file.
Reboot or shutdown - when shutting down from the shell/command line type "sudo halt" or "sudo shutdown -h now".
There are numerous ways to add roms to your RetroPie, but the easiest is to do it over network, by using a PC and adding roms to "/RetroPie/roms/gaming system folder" when your RetroPie is turned on - your RetroPie should be visible in the network devices window.
Even if you shut down the system from the GUI/menu, you can always turn the system back on without power cycling and preserving the mUSB plug, by shunting GPIO pins 5 & 6 by simply placing a jumper, a paper clip, installing a PC-style reset switch, etc (be careful to not shunt GPIO pins 1, 2 and 4 as those have voltage: https://developer.microsoft.com/en-us/windows/iot/docs/pinmappingsrpi ).
To change screen resolution refer to https://www.raspberrypi.org/documentation/configuration/config-txt.md down in the "HDMI_mode" and "Which values are valid for my monitor?" sections.
A little off-topic, but if you ever need to change your keyboard layout, type in the shell "sudo nano /etc/default/keyboard" and in "XKBLAYOUT="gb" change "gb" to the letters of you keyboard layout - for example, "es" for Spanish, "fr" for French, etc.
