That is really the wrong OS for that computer. You should be running OS 8.6 or OS 9.xxx, the way it's equipped.
400mHz is very slow.
128 mb ram isn't enough. 256 mb is considered the mininum, and 512 mb is suggested.
13 GB hard drive? With the OS on it, you can't have much free space left?
If it's working at all, it is probably so slow, it unbearable. We have an old blueberry iMac. Even with OS 8.6 on it, I can't stand how slow it is. Our's is the 333mHz model.
Good luck!
Well if you upgrade the ram to 512 you should see a big diferance. as far as the harddrive size you can alway take out the different languages and printer drivers and stuff like that