Partition 1, primary:
Windows XP, probably NTFS, 15GBs-ish
Partition 2, primary:
Personal files, NTFS recommended unless working with old LINUCES. 48GBs
Partition 3, /boot partition, 512MB, ext3 (you could easily get away with 100MBs. Just to be safe)
Partition 4, Extended Header
Extended Partition 1, 512MB, swap
Extended Partition 2, 10GBs for Debian, ext3 or reiserfs. I'd do JFS on older systems, and ext2 when installing to a flash drive
Extended Partition 3, LFS 1, 3GBs
Extended Partition 4, LFS 2, 3GBs