You could give
this a bit of a looking at.
I've improved on my suggestions in that thread.
Navigate to:
C: \Documents and Settings\{username}\Local settings\Application Data\Identities\{
hex identity string}\Microsoft\ Outlook Express
Delete all files in this Outlook Express folder in the new XP installation and copy in all the old files from the original installation.
This will give you all the POP3/SMTP e-mails but to get your web mails you'll have to re-create these accounts.
You'll have exported any Accounts settings as *iaf files and imported them into the new setup. And you can do the same with the Address Book (*.wab).
For "Rules" the way I describe is quite straight forward once you get the hang of hacking your registry.
Why you get the message titles but see no text is a fast ball. What do they look like in "Sent" items?