Change the background wallpaper

The default background image is located at \_ISO\E2B\grub\Background.bmp.gz – this is a 800x600 24--bit colour image.
Do NOT change this file because if you update E2B, the file will be overwritten/updated.

Use a \_ISO\mybackground.bmp file

To use your own image, copy your own mybackground.bmp file  to the \_ISO folder (you can compress a .bmp using 7Zip by selecting gzip as the compression type – this greatly reduces the file size - or use the E2B LZMA_Encode.cmd script will give even greater compression).
E2B v1.92+ will also recognise a file named mybackground.jpg.

Use the configuration file - MyE2B.cfg

Alternatively, rename the \_ISO\Sample_MyE2B.cfg file to \_ISO\MyE2B.cfg and change the following entries to point to your own wallpaper...
# set graphics mode - use 640, or 800 or 1024 - or specify full mode - e.g. 800 600 24 = 800x600 x 24-bit colour
set GMODE=800
set MYWBMP=/_ISO/myspecialbackground.bmp
IMPORTANT: Use forward-slash / instead of \ in folder paths. grub4dos is like linux and uses / instead of \.
MyE2B.cfg must start with !BAT on the first line.
Later versions of E2B also support .jpg files as well as .bmp files (save  as .jpg using Microsoft Paint to ensure they are in the correct format).
E2B will look for and use the specified file if it can be found, otherwise it will use the default background.

Note: The file extension is not used by grub4dos to determine it's type - you can have a gzip compressed bitmap called fred.zzz if you wish!

If you wish to use your own background file (e.g. 640x480 or 800x600 or 1024x768)  ensure that the .bmp size is exactly correct (e.g. 800x600 and not 800x599 or 799x600).
Resolutions above 1024 x 768 are not supported by E2B because E2B uses memory in the same area as grub4dos stores large bitmaps and it may crash grub4dos!

You need to set GMODE correctly (default is 800 and is suitable for 99% of systems), especially if the bitmap is an 'odd' size, some examples are:
set GMODE=1024               (1024 wide by tallest available by highest bit depth available)
set GMODE=1024 768        (1024 wide by 768 by highest colour bit depth available)
set GMODE=800 -1 24:32   (800 by tallest available that is 24 or 32 bit colour - highest available)
set GMODE=800 600 24:32 (800 by 600 by 24 or 32-bit colour - uses highest available)

in your MyE2B.cfg file. The menu size and help text position will need to be changed too. 
I strongly recommend you do not use higher than 800x600 because not all systems can support these higher resolutions (e.g. early netbooks are 800x600).
If you use 640x480 or 1024x768, the menu settings for number of menu items, menu width, etc. will also need to be changed.
Note: E2B also supports GFXBoot menus.
Tip: Choose a bitmap that has a clear area at the bottom so that help text is easily visible. Avoid a multi-coloured, high-contrast picture (e.g. lots of different bright colours and dark blacks) as it will be difficult to choose a text colour that will stand out against all of the colours in your picture! Another idea is to use a bitmap editor and draw a filled rectangle over the picture so that the menu can be displayed within the rectangle. A clear area for the menu help text underneath the menu is also a good idea. You can also add your name or company name or company logo to the bitmap itself. See the Gallery for ideas.
You can use the settings in MyE2B.cfg to change the menu position and the menu size, text and border colours. 

Menu Editor

Use the E2B_Editor.exe GUI to design your menu.
You can, of course, make a plain single colour 800x600 bitmap for the background (see 'Background fill colour' below).
Tip: grub4dos does not support all possible types of JPG or BMP files. If the background does not look correct, then simply load it into Microsoft Paint and re-save it as 24-bit colour .bmp of as .jpg.
Lots of wallpapers here!

Background fill colour

E2B v1.78+ also support filling the entire screen with a single colour. This is much quicker than loading a wallpaper file.
The MYWBMP value must start with 0x and contain a 6-character hexadecimal string (RGB):

# fill 800x600 display with red pixels : R=FF  G=00 B=00
set GMODE=800
set MYWBMP=0xFF0000

Use a JPEG file

E2B v1.72+ also supports .JPG files for use as wallpaper backgrounds as well as .bmp files.
I recommend working on an image in 24-bit .bmp format and then converting it to .jpg as the final step. Progressive (web format) JPG's are not supported (these are often used for websites as they contain a low-res image + hi-res image). If the .jpg does not work in E2B, load it into Microsoft Paint and re-save it as a .jpg file to convert it into a non-progressive JPEG format.
You can specify the name of your .jpg in the \_ISO\MyE2B.cfg file or simply name the file as \_ISO\MyBackground.bmp or MyBackground.jpg and it will be used by default.  Only grub4dos 0.4.6a supports .jpg files (grub4ods 0.4.5c does not).

Background for the Master password entry

You can have a different background for the Master Password entry - see here.

Changing background based on the day of the week

Add the lines below to your \_ISO\MyE2B.cfg file. Ensure that you have seven .bmp.gz files in the \_ISO folder named Aurora0.bmp.gz to Aurora6.bmp.gz.
# get day of week
checktime | set A=
set /a dow=%A:~20,1% > nul
set A=
# we now have a number between 0 and 6 (0=Sunday, 6=Saturday)
set MYWBMP=/_ISO/Aurora%dow%.bmp.gz
set dow=

Check for December

Use this in your MyE2B.cfg file to load a different bitmap for December
checktime | set A=
set  /a month=%A:~5,2% > nul
set A=
# 1 = January, 8=August, 12=December
if %month%==12 set MYWBMP=/_ISO/XMAS.bmp.gz
set month=

Random background

Add the lines below to your \_ISO\MyE2B.cfg file. Ensure that you have three .bmp.gz files in the \_ISO folder named Aurora1.bmp.gz to Aurora3.bmp.gz.
# get a random number between 1 and 10
set /a [email protected]% / 3277 + 1 > nul
# if greater than 3 then get another number!
if %randnum%>=4 goto :rlp
# we now have a number between 1 and 3
set MYWBMP=/_ISO/Aurora%randnum%.bmp.gz
# could use set GFX=message%randnum% instead
set randnum=


Backgrounds for sub-menus

You can have a different background for each sub-menu - see here.