Mail issue: crashes do to too many emails?

[pkusnierz]

I have 4 inboxes in my mail program and into each I receive several hundred messages per day, recently when I open my mail all I get is a pin wheel, after several force quits the computer will freeze. I have tried pulling my .plist file, and reinstalling the os. What can I do, im running this on a MBpro with 10.5
Is there possibly a professional mail app you could recommend that supports that large of a work load? I have heard of entourage and thunder bird, what about them?

Cheers

Peter