You can insert the USB cable and then in My Computer locate your new external hard drive device. It is likely to be named by it's make/model.
Then you can open My Documents and select a single folder or file.
Once selected, click the Edit/Select All option.
Right click on any highlighted item and choose "Copy".
Go back to the My Computer folder and right click on your external Hard drive device and choose "Paste"
All the folders and files in My Documents will be pasted into your external Hard drive providing the total does not exceed the 80 Gig size limit.
I don't know what email program you use. If it is Outlook Express, you can look at this page to see how to back up your messages and contact information. Export it all to your external hard drive and then in your new computer, import this same information. The export and import steps are detailed on here:
http://dwightblackburn.com/backup/backups.htmIf you have a different type of email program, post the program name here and perhaps I or someone can assist you.
By the way, what is wrong with your computer? Have you tried having a repair shop fix it? Often times it is neither difficult or expense to repair an ailing older machine.
Dwight