When restarting Windows 7 and it stuck at the black screen with the cursor blinking, the first thing is insert the Windows 7 DVD and fix the Mbr. Main reason is because it is the OEM disc and not the Retail disc was used during the installation.
1. Put the Windows 7 installation disc in the disc drive, and then start your computer.
2. Hold down Option key till all available disks are displayed and select DVD. Press a key when you are prompted.
3. Select a language, a time, a currency, a keyboard or an input method, and then 4. click Next.
5. Click Repair your computer.
6. Click the operating system that you want to repair, and then click Next.
7.In the System Recovery Options dialog box, click Command Prompt.
Type (these commands are safe)
Code: Bootrec.exe /FixMbr
Code: Bootrec.exe /FixBoot
Code: Bootrec.exe /RebuildBcd
*Press ENTER after each command.*
*Restart your computer.*