System hangs everytime trying to open something

[MasterGun]

So I have been having a trouble with mac os. The problem is that after I reinstalled it today and tried to set-up network TCP/IP or anything like that system would just hang and finder won't appear. Also when I try to enable File Sharing it just says something like "Error 3 restart your system" and same with some other apps.
My system is 400mhz AGP G4 M5183.

[MasterGun]

Okay, it turned out that it was ram issue