I have this same issue because the scaling setting is not being honored i am unable to play many of my games in full screen, the display just looks like a letterbox instead of being stretched, and returning to 'Graphics Properties->Display->General Settings->Scaling' shows that the value has reverted back to 'Center Image'
I found a solution to this from http://forums.darklordpotter.net/showpost.php?s=05190747c1b45ef811aa26b582fb9067&p=397762&postcount=4
To fix this, I lowered my screen's resolution from its native 1440x900 to 1366x768. Then I changed scaling to "Scale Full Screen". Then I changed my screen resolution back to native. I opened the Intel Graphics control panel and scaling "Scale Full Screen" sticks. Try this and let me know if it works.
EDIT: It appears that so long as you're in your native resolution, you can't adjust the scaling option. So to revert back to "Maintain Aspect Ratio", I would have to follow the above steps of lowering resolution, adjusting settings, and then returning to native.
If you have an Intel chipset integrated with Graphics Media Accelerator 4500 (GMA 4500), like the Intel Q45 Express Chipset (Intel 4 Series Express Chipset Family), you could try installing an older driver for the GMA 4500, which will allow you to choose "Maintain Aspect Ratio" in the scaling option of the "Intel Graphics and Media Control Panel" at a resolution of 1366x768. The driver you should look for is 184.108.40.2062 (220.127.116.112). For certain Dell computers with 64-bit version of Windows, search for INTEL_MULTI-DEVICE_A07_R279357.EXE, which is provided by Dell, although it might work for non-Dell computers. For other computers with Windows 64-bit, you could try installing WinVista7_64_15173, which is found in the Intel website, but I'm not sure it will work for you, because its version 15.17.3 2104 instead of 18.104.22.1682, but since it's older, it might work for you. I haven't found version 22.214.171.1242 (126.96.36.1992) in the Intel website.
Once you have found it, uninstall your current driver using the Windows Device Manager by accessing the properties of the driver, which can be found under "Display Adapters". Then, go to the driver tab and press the uninstall button. You have to uninstall both driver and its software (the "Intel Graphics and Media Control Panel"). You want to make sure that the driver's software application (the "Intel Graphics and Media Control Panel") gets uninstalled, because if you don't uninstall it and replace it with the older one, you might not be able to see the "Maintain Aspect Ratio" at a resolution of 1366x768, even if you have installed the older driver (188.8.131.522) !!
If the uninstallation of your current driver is successful, your screen will be at a low resolution. In addition, the "Intel Graphics Media Accelarator driver" will no longer appear in the list of Programs of the Windows Control Panel. By the way, before uninstalling, be sure to disconnect your computer from the internet, because once the uninstallation has been successful, Windows will try to install the latest driver from the internet, and you don't want that.
Now, install the Intel Graphics Media Accelerator driver 184.108.40.2062 (220.127.116.112). This will install the driver for GMA (the integrated graphics of the chipset) as well as its software: the "Intel Graphics and Media Control Panel", which is also known as
Intel Graphics Media Accelerator driver, like the driver itself. The "Intel Graphics and Media Control Panel" is the Graphical User Interface for the properties of the GMA graphics. If the installation has been successful, you will see the "Maintain Aspect Ratio" in the scaling option of the "Intel Graphics and Media Control Panel" for a resolution of 1366x768.
Please bear in mind you should only be using the drivers that are provided specifically by your computer manufacturer may have altered the features, incorporated customizations, or made other changes in the drivers they provide for your computer, and our generic drivers will not operate properly in your system.
I suggest that you check with Lenovo for further information on how to enable this in your system from the link below:
This is honestly the most annoying bug in the software. Any time you create a custom resolution at 4:3, you have NO OPTION to maintain aspect ratio. It's complete crap. The driver always decides to stretch full screen.
Please make this the #1 thing to fix. Make it so we can MAINTAIN ASPECT RATIO for custom resolutions.
I'm purposely bumping all aspect ratio questions so you programmers know how serious of an issue this is.
Also fix the limited 60hz problem for monitors that can go to 120hz. That's another huge bug.