At the moment I am dual booting MS Vista and OSX 86 Leopard 10.5.5 in this configuration:

Drive 1: C: Vista installation
Drive 2: D: Partition 1: Backup of C:
Partition 2: Leopard installation

The Vista bootloader has been modified to enable me to boot to either OS.

I would like to have the following:

Leopard as my primary OS and Vista as a second boot option.

I intend to wipe the first hard drive C: with the vista installation because of a virus infection and re-install later.

I also intend to move the backup vista image on D: to an external drive that leaves the rest of the space one that disk to increase the leopard partition to the disks full size.

Once I have copied the Vista image to the external drive I will delete the file and merge the OSX volume to the disks full size with these instructions I've found.

diskutil list

that listed back 2 partitions with the identifiers: disk1s1 and disk1s2 (in other cases might be disk0...)

Now,

sudo diskutil mergePartitions "Journaled HFS+" New disk1s1 disk1s2

did the trick (New is the name, it will actually be ignored).

If this works I'll have a clean C: and a full size D: with an OSX installation.

How can I now make OSX bootable as my primary OS and install Vista on the clean disk with a dual boot menu? Or would it be easier to re-install Vista using the backed-up image to C: and modify the vista bootloader for both OS's

don't you have bootcamp? on the Kaliway...