If you want to make a completely undeletable folder, here is how it can be done. (I can't find any way to delete it from the finder, though there is probably something obvious that I am overlooking). Simply (simply?!?) create a folder on a non-existant directory in the finder and give it more than 32 characters in the name using illegal control code characters, next, create two invisible folders inside that one, one inside it and the other inside the other. Second last, put the folder inside those and create a file and check the shared, name locked, and can't be renamed box. Last reboot and delete it. You will find the folder is (I think) completely undeletable from the finder and why you would want to create it anyway is beyond me. (The finder will come up with it being shared if you have file sharing on, and that you do not have enough privileges if it is off. Stuck.) You would need ResEdit to do this, Yes and Norton's Fast Find.
Practically the only way to get rid of a folder like this is to use Norton's Wipe Info program. If you Do not have The Norton Utilities, or at least temporary access to the Wipe Info Utility, DO NOT TRY THIS!