seems strange a change of monitor would cause such a problem ?what error message do you get when trying to start it,you could try starting it in safe mode,on start up after the post and diagnostics check start pressing the F8 key ,when the start up menu appears choose safe mode.obviously from there you could run diagnostics and recover your cd key.alternately you could check out sites such as ebay.com or recycledsoftware.com and purchase a new copy of 98se they are only a small cost now.