Create a partition.
U could have several OS on different Partitions and each of them will work properly.
U could split C disk and if space it's not enough u could add from ur another disk.
If u don't have any utility to perform them i'd recommend Disk Director.
This is very reliable, easy-in-use and rather cheap software.
Besides it includes recovery feature (that would ercovery ur accidentally deleted partition).
have a look
http://www.acronis.com/homecomputing/products/diskdirector/
I have xp media centre with 2 hard drives and the vista upgrade advisor says i'll need a bigger hard drive to install home premium
My two hard drives are, data (there's room for vista on there) and my c drive where windows xp and all programs are installed
I like to keep my data in a seperate hard drive for ease of transfer in new pc's.
What should i do to install vista? Should i add a new hard drive (1 for data, one for xp, one for vista) or would that confuse windows to find the directories of programs. Please help

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