I had the same problem after I upgraded to tiger, though even getting the latest version of stuffit didn't help, but someone suggested in another forum to goto preferences, click on 'Destination' and change 'Create Surrounding Folder' to 'Always'. That fixed the problem for me at least. Hopefully that will help you too.
Also you said you were restarting everytime you wanted to see the files that were extracted. They are actually there just invisible, you can always make a copy of the newly extracted folder and it should show the contents in the copy, though hopefully the above hint will make it so you don't have to do this.