You can try to use the Command Prompt with Networking Advanced Startup Option on the laptop with the damaged OS by pressing F8 at the BIOS splash screen and selecting Command Prompt with Networking. Then from another machine you can attempt to access the C:\ drive by running the following command from another machine on the same LAN by doing the following:
Start >> Run >> type \\%computername%\c$
%computername% is a placeholder for the actual name of the computer you are trying to access the drive on. If you do not know what the computer name is, you can type the following command in the command prompt to return it:
set computername >> press [Enter]
This may or may not work; i haven't been in a situation where i have had to retrieve files from the command line on a machine which could not boot the OS. There are other means of retrieving data from a laptop hard drive which are at my disposal and are much easier.
If that does not work for you, i would suggest purchasing a USB external notebook hard drive enclosure which will allow you to remove the hard drive from the laptop computer and plug it into a working machine via USB connection. You can then open the drive as if it were any other USB memory device and extract your files through Windows Explorer using the GUI interface on a functioning computer. You can also use this enclosure to wipe and format the hard drive prior to re-installing it back into the laptop. Also, it will give you access to all files in GUI mode so you can take your time and go through the entire file system with a fine tooth comb.
A sample USB external notebook HDD enclosure is here:http://www.xpcgear.com/ue25u1.html
This is the preferred method that i use to recover files on a laptop which will not boot.
NOTE: You can do the same with a desktop machine that will not boot by removing the HDD and inserting it into a functional desktop tower in the secondary HDD slot and loading it in the slave position. On desktop HDD's there is a jumper (little piece of plastic with conductors inside) which you will need to move to the appropriate slot in order to use the drive as a "slave" for file recovery or just to add a secondary HDD to your tower.
[..] Cable Select
By default, desktop most HDDs will have the jumper in the Cable Select position (indicated by [..]). The ".." represent the two prongs / pins over which the jumper will slide. There are usually 3 or 4 sets of pins which should be labelled accordingly as: Cable Select, Master, Slave. When you are putting a second HDD into your desktop machine, you want to be sure that the jumper is in the Slave position. Your master hard drive can have the jumper in the Cable Select or Master position.