Vista & XP Dual Boot - Removing XP

There's already a question about removing an OS from a dual-booting machine, but that one is about Ubuntu and Vista, and I thought people may have different/more suggestions and answers for a different set-up.

So... I have both Vista (64-bit) and XP (32-bit) installed on my PC (different partitions) and I'd like to get rid of XP.
What should I do to securely free up the hard disk XP is installed on and make sure the Vista installation does not get messed up in anyway?

PS : Vista was installed after XP.

Solution 1:

Install EasyBCD to reconfigure your bootloader and delete XP from the startup.

Then delete all the Windows XP data (Documents & Settings, Program Files, Windows etc), in case you have Windows XP on a different partition just format the entire partition AFTER taking it from your bootloader.