I do believe that is called paranoia.
Why do you think you are safer with your illegal files on a dvd instead of your harddrive?
Also, it costs thousands of dollars to recover deleted files from a hard disk. It is very rarely done, even in criminal cases.
Most file systems only remove the link to data. You would need a piece of software that incinerates the data, meaning to overwrite it multiple times. Depending on how many times you overwrite it, the data in question can be recovered by either free software or likely expensive hardware. IIRC, 7 passes makes software undeletion impossible, and 21 passes makes hardware undeletion impossible.
http://en.wikipedia.org/wiki/Data_remanencehttp://en.wikipedia.org/wiki/Undeletionhttp://en.wikipedia.org/wiki/File_deletionUnder the Fourth Amendment searches must be reasonable and specific. This means that a search warrant must be specific as to the specified object to be searched for and the place to be searched. Other items, rooms, outbuildings, persons, vehicles, etc. would require a second search warrant. I would hide the DVDs in an irrelevant area until I felt enough time had gone by.
With thousands of dollars on the line, I'd rather be safe than sorry.
Logs are not incriminating enough.
I know logs aren't incriminating enough to send me a fine on the spot, but I'd like to know if they're incriminating enough to provide investigators with a warrant, especially if my ISP complies with investigators.