Patterns, Patterns, Patterns
In order to use a bitmap as Windows wallpaper, you'll need to open the file in Photoshop, PaintShop Pro, Corel PhotoPaint, or another paint program, and save it as a .bmp (bmp or jpg in Windows 95) file if it isn't in that format already. The file must also be saved to the Windows directory in Windows 3.1. To load a background, in Windows 95, right mouse click on the desktop and select Properties/Background.
Then, from Windows Program Manager, select Main/Control Panel/Desktop/and scroll through the wallpaper files until you find the one you want to use. Make sure that the Tile radio button is selected.
I'll bet you didn't know that you can use bitmap pattern files in CorelDraw.
Open the fill roll-up. Click on the two color pattern fill icon (the checkerboard icon). Click on the current fill displayed in the roll-up. This will open a flyout menu. Select File/Import Pattern. Corel will then translate your file into a black and white bitmap. Corel isn't very subtle in its dithering between the color and black and white here. You might want to translate your file into black and white first before you try to import it into CorelDraw.
Open your file in Photoshop. Chose Mode/Grayscale, and then Mode/Bitmap. Then you can try importing the file into Corel.
Make sure that the fill roll-up is visible.
Click on the LOAD button at the bottom of the fill roll-up. Select your file.
Open a new file to fill with the pattern. Use the paint bucket tool to fill the file with a pattern.
Follow this link if you would like to play with layers and modes and patterns in Photoshop.