Files that won't delete

I recently burnt a few discs on my Macbook Pro and inadvertently created a burn folder of my entire hard drive. There does not appear to be any files in it, but it won't delete from my trash as it says there are locked items in it. BUT, the file info indicates that the file is not locked????

Also, somehow I managed to create an alias of my System folder and have no idea how to delete it. My computer is now saying that the Start Up disk is nearly full and I need to delete some files.....not sure how I managed to do this either.....all this from burning a few disks from iTunes....????

Any help would be appreciated.

FYI: I am running Snow Leopard on a late 2006 machine. I'm about to update, but waiting for the 2016 Macbook Pro to come out....any thoughts on that? Is it worth the wait.