The better way to make multi-boot

[Caio Figueiredo Abecia]

I'm in doubt to choose an effective way to make multi-boot on my pc.
I'd like to have about 4/5 SO's installed in the same hard disk in different 
partitions.
I'd like to hear from you guys, what's the better way to do this?

I know that this can be done with XOSL (www.ranish.com/part - Ranish 
Partition Manager).
And maybe by LILO,GRUB, so on..

I have in mind the following SO's to have in multiboot :

1.Windows XP
2.Windows Vista
3.FreeBSD
4.Slackware
5.OpenBSD

So.. in your opinion what's the "best" way to make that multi-boot thing ?

Thanks in advance.

Caio F.