My machine crashed and I made a manual backup to an external drive...how can i restore all my user data including mailbox data...am I screwed. I did not use time machine backup to back up my data just did a straight copy of the disk drive to a folder on my external drive
You can get your data back. It might be fairly easy with migration assistant.
There is probably some way of coping the data back & getting your mac to boot.
What OS X are you running?
What you did was drag the Macintosh harddrive Icon on the desktop to the external folder?
You may want to post your question here: https://discussions.apple.com/community/mac_os/mac_os_x_technologies
Or the discussion for your OS X version.
Whatever the case, you will be able to recover your data. You may have to copy over it folder by folder.
I believe that you can use migration assistant to move everything back. Macintosh-HD -> Applications -> Utilities -> Migration Assistant
In that case, re-install the OS. Then run Migration Assistant
What is the state of your machine? Is it working? How did it crash?