MacBook Air dual system with Windows crashed, and Mac password forgotten

The MacBook Air of my friend encountered a few big problems. Here is the story:

1. There are two operating systems in it: Windows 7 and Mac OS 10.6. She used Windows 7 exclusively (which is the reason for the 5th problem below). This may already seem awkward from the start, but please don't blame her for this..

2. Today somehow the Windows 7 cannot boot (the classical "blue screen" appeared), probably due to an error in the updating process.

3. So now we have to log into the Mac OS to do some operation on the Windows system, either to back up the data, or to edit the Windows disk somehow to repair it.

4. In order to do this, we need to install some third party tools in Mac OS (to have access to the NTFS file system; BTW, the Windows partition cannot be mounted by the "disk utility" tool due to some errors), and here is where another big problem comes about:

5. She has forgotten the password of the Mac OS system (be assured: this MacBook Air is not a stolen one), so practically we cannot install any new software, or run tools that requires a high privilege!

6. Well, by Googling I found that the password might be circumvented by using a recovery usb stick, by she cannot find out this usb stick...

7. Some articles mentioned pressing "command + R" or "command + S" during booting to enter a command line environment (I am not sure about this), which had no effect at all in our case.

By now I have no solid idea how could such a situation be solved... The possibilities I can think of are:

a. Take the laptop to an Apple repair center.

b. Try to make a recovery disk by myself, and use it to get rid of the password.

c. Try to boot the computer with an external disk (somehow made), and then edit or backup the Windows partition.

I am not sure any of them will work.

Any ideas will be appreciated!