partitioning help

Hey /tech/support.

I want to have 3 partitions to dual-boot: 1 for ubuntu, 1 for windows xp and 1 for general storage. I am told that Windows doesn't recognise Linux partitions or something so how should I go about this? (ie. do I partition it into three at first, or partition it once i install one OS on it, etc)

Also, how much space should I allocate to the Ubuntu partition and the XP partition so that I have as little space left over once I install the OS and the programs?

The Mbt will improve your posture, Mbt shoes are discounted shoes but not the imitation or damaged styles, The Mbt sale Now! Free Shipping! NO Tax!http://www.mbt-antishoes.net
The ghd iv styler hair straighener used for straightening and creating larger curls or waves,ghd hair straightener will protecting the hair shaft as well guarding your locks from the sun's harmful rays with its added UVA protection,ghd save up 50%  off,free shipping!no tax! http://www.ghdivstyle.com
The christian louboutin is the accessories brand for every super-chic fashionista, christian louboutin sale are beautiful ,comfortable and sexy,christian louboutin shoes free shipping!no tax! http://www.christianlouboutindesigners.com