Microsoft don't seem hopeful about you getting your system back easily.
SYMPTOMS
When you start a Windows Vista-based computer, you receive the following Stop error message on a blue screen: 0x0000C1F5
CAUSE
This issue occurs because the Common Log File System (Clfs.sys) driver does not fix the $TxfLog file when the file is corrupted. In addition to the Stop error message, Windows Vista may not start during startup until the offending disk is removed from the computer.
WORKAROUND
To work around this issue, use one of the following methods.
Method 1
If you have multiple disks installed, and the disk on which the $TxfLog file is corrupted does not contain Windows Vista, remove the offending disk from the computer.
Method 2
If you have only one disk installed, and if you have access to Windows XP or Windows 2000 installation media, restart the computer by using the Windows XP or Windows 2000 installation media. Next, format the offending disk, and then reinstall Windows Vista.
Note Microsoft is working on a fix to prevent this problem.