Set desktop wallpaper based on screen resolution for both WinXP and Win7

Question

I'm hoping someone can answer this for me. I would like to be able to set the desktop wallpaper based on the current screen resolution when a user logs in. I've made several .BMP files for varying resolutions with our corporation logo. But, say
if a wallpaper for a resolution of 1024x768 on a 4:3 monitor is set, then that monitor is replaced with a 16:10 monitor with a resolution of 1280x800 or 1600x900, the wallpaper looks stretched out and ugly. The only way to change it is manually on
each computer, but most end users (students) would not have permissions to do so.
I thought this question would have been asked before, but after many, many searches, I've only come across one reference that copies the background from a network share to a location on the local computer, which I found
here. In my case, the file will already be on the local computer, but I am not sure how to force the system to change the wallpaper based on the current screen resolution. I'm sure it is possible and maybe I am overlooking something very simple. I
was also thinking that this would either happen only once on first login or maybe based on user authentication (which group the user belongs to) so that teachers are still able to change their wallpaper, but students would not be able to.
If it helps, I will be deploying the image using MDT 2010 Update 1. The same base image will be used on multiple machine types (HP desktop sand laptops and Lenovo desktops) which could have one of 6-7 different monitor types connected. I'd also like
this to happen on the local machine instead of GPO or logon script as there is already a lot happening there.
I would need to be able to do this for both Windows XP Pro and Windows 7 Ent x64. The XP machines will mostly have 4:3 monitors, but there are exceptions.
Maybe what I am asking isn't entirely possible or possible at all. I, unfortunately, am in the extremely early stages of learning Microsoft Scripting (VBScript and PowerShell) to use with MDT 2010, so I know next to nothing when it comes to these scripting
processes, but am willing to try and learn.
Any help anyone can suggest, I would be extremely grateful.

Answer 1

I almost abandoned this because I thought it was going to interfere with using BGInfo. But, as it turns out, I was able to incorporate the running of BGInfo into a script that I
created. And, once I saw what 16:10 Aspect Ratio background looked like on a 16:9 Aspect Ratio screen, I was not satisfied.
I happened to use the first script that MkShffr posted from geekshangout.com, but then I added more items to it. I also created three high-res wallpaper backgrounds as suggested
by pagerwho.
My script is based on the Aspect Ratio of the current resolution. Since most, if not all, systems will get the resolution set during deployment, this was easy to calculate.
And by forcing the output of the Aspect Ratio to two decimal places, I just used a Case statement to select which aspect ratio to choose from and apply the wallpaper assigned to it. I thought about using If Then statements, but I think the Case statement
is much cleaner.
And, because BGInfo wants to change the Picture Position to "Tile" instead of "Fit" that I manually set it to in my image, I added two reg key change lines per Case. BGInfo still
changes the Picture Position to "Tile", but for whatever reason, this works. I tested this by using a laptop with a 16:9 Aspect Ratio screen. In my image, I manually set a 16:10 wallpaper because that will be the primary Aspect Ratio used in our corporation,
however we are getting more 16:9 Aspect Ratio laptops and from what HP is saying, everything will be standardizing on this Aspect Ratio.
I made sure the Screen profile that I saved in my image was loaded which includes the 16:10 wallpaper. I then placed this script in the “C:\ProgramData\Wallpaper_Change”
directory that I created in the image. I then added a registry value in HKLM\System\Microsoft\Windows\CurrentVersion\Run and created a String Value. I did this so that it would run at log in, but I didn't want it to show in the Startup Folder in the All Programs
Menu. It takes less than a second to run, but it seems to work well. I tested it several time to see if there were any anomalies, but it seemed to work great each time. I have yet to test it with a computer that is on the domain with a regular user account,
which I will be doing in the next day or two.
In the mean time, if someone want to try it out and see if it works from thier use, here is the code. I did comment out the wscript.echos, but left them in to use for troubleshooting
in the future.
-Mike
==============================
Option Explicit
Dim array_ScreenRes, screenRes_X, screenRes_Y, oIE, width, height, aspect_ratio
Dim decpos, wallpaper1, wallpaper2, wallpaper3, oShell
array_ScreenRes = GetScreenResolution
screenRes_X = array_ScreenRes(0)
screenRes_Y = array_ScreenRes(1)
wallpaper1="C:\Windows\Web\Wallpaper\TSC\Win 7 - 2560 x 1440 (16-9)TSC.bmp"
wallpaper2="C:\Windows\Web\Wallpaper\TSC\Win 7 - 2560 x 1600 (16-10)TSC.bmp"
wallpaper3="C:\Windows\Web\Wallpaper\TSC\Win 7 - 2560 x 1920 (4-3)TSC.bmp"
Set oShell = CreateObject("Wscript.Shell")
'wscript.echo "Resolution is " & screenRes_X & "x" & screenRes_Y
aspect_ratio = screenRes_X/screenRes_Y
decpos=instr(aspect_ratio,".")+2
aspect_ratio=left(aspect_ratio,decpos)
'wscript.echo "Aspect Ratio is " & aspect_ratio
Select Case aspect_ratio
Case "1.77"
 oShell.RegWrite("HKCU\Control Panel\Desktop\Wallpaper"), wallpaper1
 oShell.RegWrite("HKCU\Software\Microsoft\Internet Explorer\Desktop\General\WallpaperSource"), wallpaper1
 oShell.RegWrite("HKCU\Control Panel\Desktop\TileWallpaper"), "0"
 oShell.RegWrite("HKCU\Control Panel\Desktop\WallpaperStyle"), "6"
Case "1.6"
 oShell.RegWrite("HKCU\Control Panel\Desktop\Wallpaper"), wallpaper2
 oShell.RegWrite("HKCU\Software\Microsoft\Internet Explorer\Desktop\General\WallpaperSource"), wallpaper2
 oShell.RegWrite("HKCU\Control Panel\Desktop\TileWallpaper"), "0"
 oShell.RegWrite("HKCU\Control Panel\Desktop\WallpaperStyle"), "6"
Case "1.33"
 oShell.RegWrite("HKCU\Control Panel\Desktop\Wallpaper"), wallpaper3
 oShell.RegWrite("HKCU\Software\Microsoft\Internet Explorer\Desktop\General\WallpaperSource"), wallpaper3
 oShell.RegWrite("HKCU\Control Panel\Desktop\TileWallpaper"), "0"
 oShell.RegWrite("HKCU\Control Panel\Desktop\WallpaperStyle"), "6"
End Select
oShell.Run "%windir%\System32\RUNDLL32.exe user32.dll,UpdatePerUserSystemParameters", 1, True
oShell.Run "C:\ProgramData\BGInfo\BGInfo.exe C:\ProgramData\BGInfo\TSC.bgi /timer:0"
Function GetScreenResolution()
 Set oIE = CreateObject("InternetExplorer.Application")
 With oIE
    .Navigate("about:blank")
    Do Until .readyState = 4: wscript.sleep 100: Loop
    width = .document.ParentWindow.screen.width
    height = .document.ParentWindow.screen.height
 End With
 oIE.Quit
 GetScreenResolution = array(width,height)
End Function