Re: best way to partition 250GB for dual boot windows xp and ubuntu
I'd go for:
125GB shared data
If you don't have much shared data but lots of Windows games and stuff:
50GB shared data
Having said that, I'm running XP and ubuntu (did have 9.04, tried 11.04, settled on 10.04 for the time being) split about 50/50 on a 1TB drive. I used to merrily dip in and out of the Windows partition and share data. I now have a lot of data on an 1TB disc formatted as NTFS and continue to read and write to this from both OSs without mishap so far. Risky - possibly. Backups - definitely.
AMD Phenom Quad 9650, 8Gb RAM, (2 x 1) +(1 x 1.5)Tb HDDs; 64-bit Lucid (ʍoʃs ʎpooʃq ooʇ sɐʍ ʇı ʇnq ʎʇʇɐᴎ pǝıɹʇ I); Dual-boot Win XP Pro 32-bit (although mainly use WINE or VirtualBox). HP t5730 with 1GB RAM and 160GB HDD running xubuntu 10.10.