Thanks for the heads up on ACAD 2K05 (2005).
Is that the Lite version (sure it will be similar for the full version, too).
I've worked with 2002 LT, running under Windows 98 (SER2). No Plot lockup problems, but a few others here and there.
Company's President was running same version on a semi-new machine using XP (this was early 2003), and there were lots of problems... mostly from this Person's lack of Computer / ACAD knowledge, but that's another story!