Posted 01 January 2013 - 13:40
Just did this yesterday.
In short, it all depends on where you told Mint to install its bootloader.
Ubuntu and its variants are going to want to install it to "sda" by default - so it becomes the primary bootloader. Note "sda" without a number after it means the MBR of your disk.
Assuming you're currently happily using the Windows bootloader, I would change this option to "sdaX" where X is the partition of the linux install.
This way, you use the Windows bootloader (configured later via BCD) to load the GRUB bootloader of Mint which resides on a partition now.
Seems to me that this configuration gives you the most flexibility down the road and easiest recovery path. Also, I find the Windows bootloader much less susceptible to problems than GRUB in a (Windows) dual boot situation.