I finally setted the Windows registry right! It fought me hard but after counless time with REGEDIT and with a little help of Norton Utilitie's WinDoctor, I think that (so far) Windows 98 is stable.
Now, I'm re-installing applications and getting enough energy for the next step: Windows 2000 base install.
So, finally, who's in charge? (the computer, of course!..... :-)))) )....