Probably dumb question but in Trash...

No. Or, rather, you have to do it manually: Create a temporary folder somewhere other than the trash, drag everything you don't want to delete yet into it, empty the trash, then put the temporary folder (and/or its contents) in the trash.

As for iTunes and iPhoto, it depends on how you're deleting them. In iTunes, if you delete a file from the library (deleting one from a playlist only removes it from the playlist, it's still in the main library), iTunes will ask you if you want to move the original file to the trash or not. If you tell it to, the file is in the trash but of course is still taking up space until you empty the trash. If you don't, the file is still hiding in the iTunes library folder, though iTunes itself won't show it. These are kinda annoying, since there's no easy way I know of to check for them if you accidentally didn't have it toss one.

iPhoto is different; it has its own internal trash can that works similarly to the main one--stuff you delete goes in that trash, but is still there until you tell iPhoto to empty ITS trash from within the application.

That's what you were asking, right?