PC version Fans have made a PC version. Some are still early, so read the project page first.
Fans took Buffy the Vampire Slayer: Chaos Bleeds apart and rebuilt it so it runs natively on a computer, often with widescreen, higher frame rates and mods. Here is the project we know about:
Unofficial native PC port of Buffy the Vampire Slayer: Chaos Bleeds (Xbox). Bring your own disc.