Restoring just the bios using disc?

You haven't the slightest idea what you are talking about take your computer to a shop the disk has absolutely zero to do with bios it is your operating system what you need to do is learn a little bit about computers before you start messing around take it to a shop spend with the $75 are you're going to wind up ruining your computer and wishing you would spent the $75

Any proper restore of Windows 7 is going to want to replace all the operating system files. This will normally mean that you will have to restore all the extra drivers and applications that were on the PC. You can save your actual data files, but as many applications keep information in the Windows registry, this information will be lost. Personal data such as videos, pictures, music and documents should already be backed up on a separate removable external hard drive. If your disk drive fails, then your data will be lost if you don't have a backup.

If System Restore is turned on and there are restore points going back far enough, then you could explore these to see if this helps improve the PC's operation.

Ideally, you will have Windows 7 and the applications in C: and keep your data in D: so you can repair one logical drive without affecting the other.

Finally, you say it takes 1 to 2 hours to scan the drive. It is now 14 hours since you posted the question. Was it worth the wait?

BIOS is firmware, and probably isn't on the restore disc.Best you can do is just a full systems restore. If you're concerned about the system freezing, don't be. You can always start over.