My M6809 Crashed!

I've had my M6809 for about a year. I use it mostly as a desktop replacement with external DVD+RW, external mouse, keyboard, monitor, etc. It had been running kind of slowly, and the hard drive was constantly getting majorly fragmented, but last week I got an error message saying that Windows could not start up because an file was missing or corrupted. It wouldn't even boot in safe mode.

Because I was on the road at the time, I didn't have my backup and recovery disks, and Norton GoBack was no help either. So I ended up taking it into a local Best Buy (the retailer from which it was purchased.) They couldn't get it fixed either, but all of the tests indicated the hard drive was still OK.

Their solution ended up being: having me buy a Seagate 100GB portable external hard drive, removing the hard drive from the shell and putting it into the computer, then putting the old 80GB hard drive into the shell and using it as an external drive so I could recover files from it. They got Windows XP loaded (apparently from a Dell recovery disk) and I can get into Windows and some other things, but of course I don't have any of my software, etc., all of which will have to be reloaded when I get home. (And I'll also restore Windows XP again from the eMachines disks.) By the way, although it was still under warranty, and I also have the extended Best Buy warranty, they wanted to charge me for restoring the operating system since they said it wasn't caused by any defect, but they ended up only charging me for the hard drive, despite having worked on it for over seven hours! (The only driver they couldn't get to work was the modem driver, although I seem to be having problems with the DVD writer as well-- when it's empty, Windows recognizes it as a DVD+RW drive, but when I put a blank DVD in, it changes to a CD-RW drive, and it refuses to write to the blank DVD.)

I'm no computer expert, so I thought I'd throw these questions out to those of you who are:
-- What could've caused the problem in the first place? The Best Buy guys thought it was a virus, but I've now scanned the old hard drive several times with different programs and no virus shows up. (I had an updated version of Norton Anti-virus as well as ZoneAlarm and several anti-spyware programs running.)
-- Should I leave the new hard drive in place? It's a 5400 RPM with an 8MB cache--is that equivalent to what was removed? (I know that it's 20GB larger, too, of course.) The alternative would be to try to get the old hard drive restored (after I've backed up the data, of course.) Another thing relating to the hard drive-- the new Seagate is formatted with FAT32, while the old one is NTFS. What should I do about that?
-- Because it was always running slowly, I'm thinking I probably need more memory. Can someone point me to the instructions for upgrading the memory?

Thanks in advance for any advice!

J-Man Notebook Enthusiast

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