Use find in conjunction with exec, e.g.
Code:
find . -mtime +5 -mtime -7 -exec rm -i {} \;
This will remove all files last modified between 5 & 7 days ago.
Note that I've specified the -i flag to rm to make it prompt before removing a file. This is always a good idea when doing magic with find + rm to make sure you only remove the files you want to remove. Remember, there's no undelete on the command line (alternatively you could mv the found files to another directory for later perusal/removal, e.g.:
Code:
find . -mtime +5 -mtime -7 -exec mv {} ~/files_for_deletion/ \;
See "man find" for more details about what you can do with find. it is a very powerful tool!