...I forgot to select true letter G for the card, and sellected C drive Die !!
That's VERY bad...but i'm sure, you know that NOW

The bootable.exe for CHDK writes into the first 512 bytes of the medium, this area is called "boot sector", Master Boot Record MBR on x86 architecture. I think the winbootabel.exe should do the same, only from a Windows GUI - if you mean the tool from the russian forum (i never used it by myself).
You could only access your drive c: when the MBR contains a vaild partition table.
If you don't have a backup of your harddiscs boot sector (i don't think you have that), you can try to write a new MBR to your disc, but first stop and read this:
If the files on your drive are really important you can give it to a data recovery company,
they could normally recover most or all of your files, but you'll pay money for it ! Wikipedia: Data Recovery...if you want to try it by yourself, don't forget:
All actions can destroy all your data, after that a data recovery specialist can't help you anymore !!!
So - if you're
REALLY sure that you want to try to repair it by yourself:
- boot your system from a MS Windows XP installation CD
- select "
r" ("Recovery console")
- select your drive, your Windows installation & insert your administrator password
- on the recovery console you can get a list of all commands with
help- you can use
diskpart to have a look to the partition table (but do not try to change something there !)
On the prompt of the recovery console call each of the following commands, read & confirm the messages...
fixmbr c:
fixboot c: Then type
exitand your system will shutdown...with some luck it starts up again, otherwise you can try other ways to recover your data, e.g. with a Linux Live CD or a recovery software...
You can also use a Windows PE system (a Windows system running from CD), e.g. made with
BartPEGood luck !
*EDIT: a free & powerful data & partition recovery tool is
TestDisk, could also be helpful...