Hello again
You can do two types of installation.
1/ a full installation - will remove all existing data from win Vista partition and replace with Mageia.
2/ a dual boot installation. you retain your Vista O/S and data, and have Mageia alongside. You can access your Vista data from Mageia but not the other way.
If you choose the dual boot option - very popular with new Linux users, you will need approx 10-20G for the 3 Linux partitions that has to come from your Vista partition. [ Home, swap , / ( system ) ]
Do you have this much spare on this partition?
Yes.... excellent.
You will need to resize the Vista partition [ shrink it ] .
Parted magic is an excellent tool for this:
http://sourceforge.net/projects/partedm ... o/downloadif you havent already read this also :
https://wiki.mageia.org/en/Newcomers_start_here