Dell 533 Mhz 256M memory Windows 2000Pro up to date MSOffice

After defrag and WD harddrive Datalifeguard Tools--Try to pull up Word and it tells me to insert disc 1 of office; I do and then it says "Error applying transformers, please verify that the specified transformer paths are valid." Someting must have gone wrong in the registry or something.
I try to -add/remove- MS Office and it will not do it. It gives me the same message. Before I did all the above stuff I used a defragging program and a registry cleaner but I don't want to say which ones as it might not be their fault. There is not an icon for how I feel about this.
thanks
g

With your registry cleanup program I assume it makes a backup.If so,restore the backup.