You're going to need another PC to burn the disks necessary to work throught the steps for Troubleshooting Windows 7 Failure to Start.
The Disk is provided in Step 5 to use for Repairs or possible Reinstallation.
I would start with the suggested 3 Startup Repairs from the DVD's System Recovery Options
If it doesn't offer to System Restore and fails to repair, then run System Restore from the Options list next.
Then run SFC /SCANNOW Run in Command Prompt at Boot
from Command Prompt in Options list. See if it repairs damaged System files, if it will then start, or run Repairs again.
Then continue with the other steps in tutorial if necessary.