check the readme that comes with softice (i believe it is an html file) and compare your build of windows 2000 with the ones they've listed as compatible.
If yours wasn't listed, like mine, then you might be out of luck. I was unable to get breakpoints on APIs working at all. However i could get breakpoints on messages working, which wasn't good enough to crack with
Use a program like Soft Snoop or W98dsm and see what functions are imported that look like memcpy. With softsnoop you can just run the program and see what apis are being called with is handy for that sort of thing.