How to partition the HD in order to give Leopard the best chance?

[oleaaj]

(This was also posted in InsanelyMac)

I want to give Leopard every chance I can to work, so I am going to erase my primary 80GB HD (SATA), repartition and reinstall.

I would like to install WinXP (getting rid of Vista), Leopard 10.5.2, and possibly Ubuntu.

I have an Asus 8N... de luxe motherboard, AMD x2 3800, 1 80GB SATA HD, 1 250GB SATA HD.
(Will find the exact specs if needed)

The questions:

1. How should I partition my drive?
2. Which OS goes into which partition
3. Would it be better to use several different HDs?
4. Which OS should be installed first?
5. Is it possible to have just one bootscreen? Be it Darwin/Grub/or whatever windows uses...

Some of this has probably been covered in other forums, but I could not find a good guide. If you know one, please post the link!

I thank you all in advance!