Windows 7 Crashed and almost Unfixable By Start Up Repair or System re

Well I'm a noob in fixing computers , i Have a PC with i7 Processor running Windows 7 Ultimate and one fine day a blue Screen dropped saying a lot of things like Windows has Crashed, Dumping Physical memory, And It isn't working since then , It says Start up repair Can't fix this Computer,Details:

Problem event Name : Start Up Repair Offline
Problem Signature 01 :0.0.0.0
Problem Signature 02 : 6.1.7600.16385
Problem Signature 03 : unknown
Problem Signature 04 : 29
Problem Signature 05 : AutoFailover
Problem Signature 06 : 1
Problem Signature 07 : OsVersionMismatch
OS Version : 6.1.7600.2.0.0.256.1
Locale ID : 1033

and when i tried to restore it to an earlier point it says " System restore Failed While copying the registry from restore point And the error code is (0x80070570),
and i tried it with the Installation Disk but no luck :/ Whole PC works on a 500GB HD Split onto about 3 Partitions and the C: Partitions size is Approx. 70 Gigs, Well, i tried to access the rest of the files Somehow and the other Partitions Seem to be fine , But the files on my Crive not Accessible...:/

I just wanna know if theres anything i could do within the settings , without having to reinstall The whole OS,

Could i do anything from the CMD ?

If i had to reinstall the OS, is there anyway that i can back up all my files on drive C to another drive ??

Carefully proceed with the steps in Troubleshooting Windows 7 Failure to Boot and post back after each step what your results were so we can provide more troubleshooting steps if necessary.