on run {input, parameters}
 tell application "System Events"
 activate

 --BEGIN Config
 --You should only need to edit these variables
 set myAccount to "your.email@here"
 set myMailAccounts to {"Inbox", "1 To-Do", "2 Wait", "3 Completed", "Archive"}
 set myDefault to {"1 To-Do"}
 --END Config

 choose from list myMailAccounts with title "Open Mailbox" with prompt "Choose Mailbox" default items myDefault
 set selectedMailbox to result as string
 end tell

 --Activate Mail in case the dialogue box was cancelled out of
 tell application "Mail"
 activate
 end tell

 --loop through options and decide which mailbox was selected
 repeat with i from 1 to count of myMailAccounts
 set this_item to item i of myMailAccounts

 if selectedMailbox is this_item then tell application "Mail"
 --if this mailbox was selected, open it
 activate
 set s to selection
 repeat with eachMessage in s
 move eachMessage to mailbox selectedMailbox of account myAccount
 end repeat
 end tell
 end repeat
end run