This problem is usually fixed by replacing the oleaut32.dll file through System File Checker.
I've included the steps "just in case":
Go to Start>Programs>Accessories>System Tools>System Information, and then select Tools>System File Checker. Click on "Extract one file from installation disk" to enable it, then put "oleaut32.dll" (without the quotes) into the "Specify the system file you would like to restore" field.
When it asks you where to look for it, first try C:\Windows\Options\Cabs, click OK. If it says it can't find the file, tell it to look on the Win98 installation CD (which you will then have to put into the CD drive, of course).
Tell it to save the extracted file in C:\Windows\System.
Post back with the results.