Try booting into
System Recovery Options on the F8 menu as shown in Option One in blue link.
If these fail and you cannot make a Windows 7 System Recovery Disk or don't have access to an Installation DVD, try booting into free
Partition Wizard bootable CD, rightclick on your Windows 7 partition to see if data is still intact. If so make sure partition is marked Active then click on Disk # to highlight it, from Disk tab select Rebuild MBR, Apply steps, reboot.
This may preclude the need to run
Startup Repair 3 Separate Times to repair or rewrite the System boot files to the Active partition.
If this fails, what is your licensed Windows 7 version printed on the COA sticker? 32- or 64-bit?