Did my suggestion of installing the IDT audio driver resolve the sound issue?
If you can't run the system file checker that means that your Windows 7 installation is severely damaged.
You may have to save your documents , data , photos and music externally and then choose between a recovery or a repair installation with a Windows installation DVD. That is likely to be the only fix for that issue.
A recovery can be done with the USB HP recovery media or recovery disk set you should have created some time ago.
You can download the matching Windows 7 iso from here. The one you use must match exactly what is shown on the Windows COA on the bottom of your notebook. The 25 character Windows license activation key must be visible to use this method. You will also need Magic Disk to mount the iso to a virtual DVD drive. You will need to download and use Microsoft's USB\DVD download utility to make a USB or DVD installer from the ISO that you have mounted in the virtual DVD drive. When you have created the USB (preferred method) installer you can follow Britecs great tutorial to fix your current Windows 7 installation on your notebook's hard disk.
Repair Install Windows 7 by Britec
Best regards,
erico
