Recovering a Mailbox?

Dear Apple Users and Support,

I recently did an idiotic thing and managed to turn one of my mail boxes where I collected mail from 2-3 of my friends totally into junk. I remember highlighting all the message and was attempting to move them to a new mailbox/folder but then accidentally hit JUNK. Nothing happened so I assumed that I was alright. But when I opened my MAIL app yesterday I noticed all those messages were gone. I'm assuming they were marked as JUNK and due to my settings erased them when I quit the program.

So my question is, how can I get those letters back? I had time machine back up about a week ago. Which would mean I would only lose like 5-6 messages total in the end. Is there a way I can use TIME MACHINE to get a specific inbox back in my MAIL?

Also, my other option I think is because I pull my mail from the Gmail server and I leave the mail in Gmail, I might be able to pull all the messages that are still sitting on Gmail with the addresses that I need. Is there a way I can tell my MAIL to get all the messages from certain addresses off the server again from Gmail? I assuming there's a parameter that shuts down after retrieving the mail the first time, because otherwise it would constantly pull the same messages off the gmail server.

Finally, for the past year, my MAIL app has been acting up, and I can never "Quit" out of it as normal. I usually have to Force Quit out of Mail to shut it down. Like 90% of the time it wont' shut down without me Force Quitting it. Any suggestions to stop this problem?

Thank you for any assistance, those e-mails mean alot to me!
Thanks!

Tomes