Can I retrieve files that I overlaid by dragging the files from my
floppy to 'My Documents' ? and how can I do this?

The functionality of Windows Explorer, the file manager for Microsoft
Windows, is limited to undoing moves (Edit/Undo Move or Edit/Undo
Copy).  It will do little in recovering files that have been copied
over.

Your ability to get back the "old" overlaid files on your hard drive
is also limited by time or disk activity.  The more the drive has been
used, the more likely it will have overwritten the old version.  But
if you act quickly, it's possible to recover the old versions with one
of the following tools:

File Scavenger, $40.  May wish to try the demo version, as it recovers
files up to 32K bytes,  It is for sale on this Tucows catalog page:
http://www.tucows.com/preview/245887.html

File Restore, $39:
http://www.winternals.com/products/repairandrecovery/filerestore.asp

LC Technology has File Recovery for Windows is $59 that covers Win95
through Windows 2000 and XP versions:
http://www.lc-tech.com/filerecovery.asp

A Google search strategy to find software and even reviews is:
Windows + file + recovery
or 
"Windows XP" + file + recovery
Windows + file + recovery + reviews

Good luck with the process and rest assured that many of us have done
the same thing!

Best regards,

Omnivorous-GA

lots of info given - maybe even a great answer! (I was of course,
hoping for an easier answer!) thank you

BRS -- the problem has existed as long as we've been copying files. 
It was what made Peter Norton's reputation early in the days of the
PC: a utility to UNDELETE a file!

Thanks for the rating!