welcome to the forums.
vpc7 on a G5 works well, especially for running windows 2000. more memory is better if you plan to use it much. above 2gb is what i would recommend.
i was running vpc7 on a dual 1.8 with 4gb, placed the vpc windows image on the second hard drive, gave windows max memory and video ram, and it ran fine. think mid range dell pentium 4 system. not going to win any races, but very usable.
i never found a better way to do windows with a PPC system. best of luck.