To change the font, start a theme using an existing theme, then click on Edit > Options, then the Fonts tab. Click on Main Font and select the font you have installed in Windows, change the font size if necessary, then click OK. You will likely need to create your background in a graphics editor (Photoshop or GIMP for example - save as a PNG file in the screen dimension you are wanting to use (640x480, 800x600, etc.). To remove the menu bar, you can delete this in the main layout of the theme editor. You can also move around the dates and times (or remove them if you wish). You can also reposition the Image and Image2 positions (Image displays your logos and videos, Image2 generally your bezels and cabs). Keep in mind that you will need to create bak files for each emulator and other parts of GameEx. It's going to take some trial and error but once you get started it will become second nature again.