I have Vista too and there is an XP label in one of my partitions...I don't think he has XP.
Assuming you are trying to dual-boot, follow the instructions in the below link to create space for Mint from your Vista 143GB partition: http://www.howtogeek.com/howto/windows- ... -problems/
(you don't need to go below the 'Using Linux to Resize' heading as you will have Mint create your partitions) - looks like a lot but it is not bad really!
After you create the free space, you will install Mint there.
-Note: Do not choose 'side-by-side' install method after you start the Mint install, best bet is to choose manual so you can designate your partitions (swap, /, /home or /data, etc...) and the size of the partitions
-Note2: If you do not want the Mint booter (Grub) to take over the Vista booter, download and install EasyBCD and follow instructions at below links:http://neosmart.net/wiki/display/EBCD/Linux
If any questions, just ask.