imemilysteward You may need to manually install .NET Framework 3.5. Click Windows key-R, enter appwiz.cpl in the run box, click "Turn Windows features on or off," and the .NET runtimes will be near the top of the list. Click the empty box to install .NET 3.5, and restart your computer. If the box is filled in, click it to uninstall, restart the computer, reinstall it the same way, and restart again.
If that doesn't help, please provide a dxdiag. Click Windows key-R, enter dxdiag in the run box, wait for the scan to finish, click "Save all information," and save the file to your desktop. From there, you can attach it to a reply using the paper clip (Attachment) icon included with the other formatting buttons.