Michael,
There are a number of possible causes for what you're experiencing, and
you're not the only one having that problem.
Some possible causes, in no particular order:
- hardware problem that is only currently manifesting in this manner
- bad third party driver that may be unrelated to Mail but still affecting it
- unfortunate email mailbox configuration that triggers bugginess in Mail (might be worth trying the "rebuild mailbox" option in Mail)
- overtaxed resources from too many loaded apps (determine out if you're in virtual memory hell while Mail is running)
- problematic input manager plugin
This is a situation where I'd normally recommend you make a Genius Bar appointment, but I'm not sure there are any Apple Stores near you. There are actually all sorts of things you can do yourself to rule out some of the above possibilities, but I'm not going to write a book about it, here.
Mail works fine when it works, but when it doesn't work, it can drive people straight out of their minds. Unfortunately, I've never found a better email client
on any platform. They all have their drawbacks.
Martin