First thing I would do is set up Outlook Express - download version 6 - and try that. At work I use Outlook for my diary, contacts and e-mails and would be lost without it. However, at home I use OE6 - it works fine. You can also change to a web-based e-mail like BT/Yahoo, where you work on a web page on Internet Explorer.
It's a bit drastic to change computers because of software problems. Don't you have a contact/friend/etc that could look at it for you? - it may something ridiculously simple, or a straightforward disk/system cleanup, defrag, something like that. I'm not an expert by any means, but that is the way I would approach the problems as a first step. Certainly the cheapest, and you can setup OE6 in a very short time because the settings you already have for Outlook - it is a case of transferring them across by hand.
If you get stuck in trying that, there are plenty of real [and friendly!] experts here on this site who will lend you a helping hand. Good luck!
FJJP