Backing up offline hotmail

I tried doing a search on this problem but had no luck finding anything very helpful either here at MG or online and yet I suspect this should be pretty easy.

I've just built a new system for my girlfriend. The OS is WinXP Home w/SP2. Her internet access is MSN dialup and so she uses MSN email/aka hotmail. She's been using it for quite a few years and has 7 display pages of email headers for all the email that that she's moved into folders on My Computer to preserve and be able to access offline. What's the best way to insure these get copied to her new hard drive and put in the proper place. I want to make sure everything remains in synch also -- her address book especially.

I thought of moving the emails back into some specially-created-for-the-purpose online email folders at MSN, but surely there's an easier way to do this? If I just copy all the folders containing files with .dbx extensions to, say, a flash drive and then put them into the same folder structure on the new drive will that work? Or if I run the settings and preferences Wizard (or whatever that's called -- to move settings from one install of Windows to another) will that migrate her offline hotmail emails also? (I'm doubtful that's the case, but haven't ever used that preferences/settings wizard, so don't know exactly what it does and doesn't cover.)

Or is moving her offline hotmails back online into her MSN email folders from her old machine, and then transfering them back into offline folders onto the new machine really the easiest and most foolproof way to go? And if it is, how can I make sure she's allowed enough space to store 7 pages of headers worth of email (some with photo attachments) in her MSN account. Or at least be able to estimate how many I can move at a time. (But surely I don't have to do it like this??? Must be an easy way to back up and move the proper files containing her offline hotmail so that it doesn't get screwed up and is readily accessible on the hard drive in her new machine.) I haven't seen any indication of how much storage space she's allowed for her MSN email account, nor anything indicating how much she's currently using.

Can post full system specs for her new machine and old machine, but seems to me that's not relevant to this sort of problem.