What are the names of the folders?
Many folders and file cannot be removed because the programs that are inside of them are being used. This is normal. Generally, it's a bad idea to go around deleting folders because you think that you don't need them. You said it yourself - you are a novice. If you don't *know* what you are doing, you shouldn't be doing it.
Do you have active virus and spyware protection? If you do and the system is clean, you should leave the folders alone.
Are you running out of drive space? If so, you should consider a larger drive. We can help with freeing up space and advice on upgrading your drive, but you need to provide more info.
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