[GRASS-windows] Installing GRASS on Win XP

[geoff carver]

I have been having trouble reinstalling GRASS on XP.
I have downloaded the stand-alone, and via OsGeo4W, and installed,
reinstalled, removed, rebooted, reinstalled, etc., in various different
sequences without success.
QGIS also isn't working.
When GRASS starts, the black console window comes up, and among other things
says "g.dirseps" is not recognized as a valid command, then refers to a
number of Python commands, before opening the logo window (nice map), before
shutting down.
Any ideas?