mail unresponsive

my mail is hung up and won't do anything. all mail disappeared (had over 50 emails) it is trying to send a message, which i cannot even see under drafts or anywhere. it does not shut down unless forced. i cannot open account preference or anything else. i have done a "repaired premissions" but it did not help.

i can go to my isp's website and pull up my email account and they are all there. i have sent myself an email thru their website and it comes through with no problem... just not to mac's mail.

any suggestions? thank you.