You can do it, but you need to play around with the command line. The usual disclaimer about screwing up your system applies.
Run Terminal.
At the prompt, type "diskutil list" (without the quotes). This will list all the partitions that can be identified.
Make a note of the names and file systems of your Windows partition(s). I have two partitions for Windows, named "System" and "Data" and both are NTFS formatted. Yours may be FAT32.
Type the following (without the quotes): "sudo nano /etc/fstab". At the prompt, type your password.
This will start Nano, a Un*x editor.
For each drive you do not want to auto-mount at startup, type the following:
Code:
LABEL=<name of drive> none <filesystem> ro,noauto 0 0
Replace <name of drive> with the volume name of your Windows drive.
Replace <filesystem> with the type of file system - either "ntfs" or "vfat" (for FAT32) (again, without the quotes).
Replace "ro" with "rw" if you want to be able to write to the partition - FAT32 only.
Press CTRL-O to save, ensure the file name is /etc/fstab and press ENTER.
Reboot.
Your partitions should no longer be mounted.
If you want to check, drop into Terminal and type "mount" and press ENTER. Your Windows partitions should not be listed. If you do want to mount them, you can do so from Disk Utility.
