error loading explorer.exe. SHLWAPI.dll

I have a PC that i installed Win98SE on and then went on to install IE6. This
PC is not on the internet and the only reason i need the IE6 was because i
have a HP Deskjet 3745 that needed a version of IE that was over version 5.
After about a week of the PC running ok, it was rebooted and came up with the
error:

Error loading explorer.exe. You must reinstall Windows

After clicking to get past this another error popped up saying;

Error starting program
C:\windows\system\SHLWAPI.dll not found

I have read through other fixes for this and as of yet have not tried any
because i am trying to find out what version of the above file i should have.
Before i installed IE6 i had version 5.00.2614.3500 and after installing IE6
i had version 6.00.2660.0000. This looks to me like a newer version, and so i
cannot see why it is causing a problem. Surely me extracting the original
file from the Win98SE CD will make the file too old. I am getting very
confused with all this. And any help as to how to get the PC booted up and
working would be great. If i reinstall Windows98SE i still need to have my
printer working and so will need IE6 again. This in turn will cause the same
problem. Please help me!

Gary