Mail.app thinks I'm a new user

My laptop locked up (black screen, spinning beachball), and after leaving it to see if it would handle whatever it was doing on its own overnight, I went and held the power button down to force it to shut down.

When I brought it back up, everything seemed okay until I went into Mail.app ... which is asking me about my account information, as if I had never used it.

I unfortunately don't have a recent backup. I see that I still have a ~/Mail directory, which looks to have lots of my local folders defined.

Should I go through with the 'new user' setup, to see if it finds my existing local mailboxes, or is there some other recommended procedure for this process?

I'm running OS 10.6.8, and Mail.app 4.6. (And before I get lots of comments, yes, I know they are old, and yes, I know that the newer OSes are free upgrades)