Bid Buddy will currently install on only your "C" drive. Soon I will release a version which installs on the drive of your choice, but I won't release that version until I've tested it fully and am completely satisfied that I'm not going to create a support nightmare.
Bid Buddy will run on any version of Windows- from Win95 to WinXP but here is the hardware/software that I recommend with the latest release.
Operating System: Windows XP with a "C" drive partition
Hardware: Pentium III or greater running at least 1GHZ, 256mb of memory, 100MB of free hard drive space, color printer
I currently successfully run BB on my laptop which has a PIII-800mhz, 256mb of memory, and Win-Me
Bid Buddy will run on the Macintosh under Virtual PC