Have you updated your virus scanner and run another scan? Generally, if you cannot delete a file or folder, it is because the file/folder is in use. If, for example, the virus in question is still rampant upon your machine, it may be causing the folder to remain used. Also, I agree with Sgt_B that you cannot delete a 0 Kb folder, which makes me think that it is, in fact, not a folder, but rather a file which "looks" like a folder. What you may want to do is also open the batch file which infected you in Notepad so you can see exactly what the file did. If you can decode what the virus/trojan exactly did to your system, you may be able to simply go backwards and fix everything. Hope that helps.

AJ