The old OS debate. That's what got me to register.
I dual boot because 2K and Linux let you run apps that are either MS-only or Unix-only. There is a program for Linux called wine that runs some Win32 apps, but only a handful. Interestingly, it runs SE4 well (the combat screen does slow down a bit), though I had to install (1.0 on CD) and patch (to 1.49) under Windows since wine choked on the installer and the patch.
The only drawback to dual-booting is that Linux can't write to NTFS partitions, so my 2K installation is on a FAT32 filesystem.