In order to restore your thinkpad to the factory restore, you need the CDs
It is possible to boot it via usb-ide and cdrom. But additional dos usb cdrom driver need to be loaded. This is done through devload which load *.sys driver dynamically.
copy all your files from A: to RamDrive
devload usbcd.sys /d:usbcd001
mscdex /d:usbcd001 /l:e
That's all, your usb cdrom is not accessible with your thinkpad
Then, set the neccessary PATH and execute recover.bat from the cdrom drive.
[assuming c & d drives are cdrom and ramdrive resp.]
End of story