Hello rtsrangel and welcome to Seven Forums.
If you created a System Repair Disc you can use it to boot your computer. Then you can access various System Recovery Options such as system restore. You could then restore your computer to an earlier date/time prior to when you installed the directx sdk.
System Repair Disc - Create
Or perhaps your computer manufacturer created a hidden recovery partition. You can usually access this partition by turning on your computer and immediately clicking the F8 key (top of keyboard.) Keep clicking until you see the Advanced Boot Options screen. From here you should be able to select Repair Your Computer.
System Recovery Options
Please post back if any of this helps or not.