Reinstall SL - Lost Data & Documents

Question

Good afternoon,
My father has a MBP with Snow Leopard 10.6.8 installed and in the past week it became slow to the point where it was hardly usable.  The only 3rd party apps were VMFusion and Microsoft Office.  He told me that he did the software update recently after months of putting it off.  I figured that it might have been an issue with doing the software update through the apple dropdown, because I had the same issue with my MBP months back, and it went away after installing the combo update.  I ended up downloading the combo update and in the middle of the update, the comp crashed.  From that point, I could never get back to the desktop, it always got stuck on the grey screen upon bootup.
Next, from there, I went step by step down the fix you mac found here...https://discussions.apple.com/docs/DOC-3353
None of the items worked until I did #8, Reinstall OSX.  After doing so, that got me back to the desktop, however, with every click, I would get the spinning wheel of death and nothing would open.
Now I just restarted again and it takes me to the login screen (name and password) and my dads account has vanished?  The computer was setup as a single user.  I went into the "reset password" when booting from install CD and it shows nothing about his account either.  The only account that is listed is the System Administrator.
The only time I can get into the desktop is if I sign in as the System Administrator, however when I do so, it does not show any of his documents.
The most important thing is that I retrieve the items that were in "My Documents" as they were pretty important to his business (which is why he should have been backing up in the first place).
I dont get how his account has vanished along with his documents after reinstalling, from what I understood, everything should have been left untouched.  Any help anyone can provide, I am greatly appreciative.
Thanks,

Answer 1

I get the spinning wheel of death
Troubleshoot the spinning beach ball
the computer is still really slow
Sluggish Finder - Bunch of icons on your desktop?  An overcrowded desktop slows down your Mac.<P>
Get rid of needless Finder calculations - Open a window in Finder/View/Show View Options:  ensure "Calculate All Sizes" option is unchecked.<P><P>
Internet related - It's likely that your broadband connection is the bottleneck.  You can check your speed on http://www.speedtest.net
to see how fast your connection is.  If your web browser specifically performs slowly, quit and relaunch it.<P> 
If browser remains sluggish, empty its cache.<P>
Safari/Empty Cache<P>
Firefox/Preferences - select the Network tab of the Advanced preferences and click the "Clear Now" button in the "Offline Storage" area.<P><P>
Application related - Launch "Activity Monitor" - Applications/Utilities - click the CPU heading and see what float to the top.  If an application takes up a large chunk of CPU and won't let it go, it could be dragging down your Mac's performance.  Quit it by clicking the Quit Process button at the top of the Activity Monitor window.<P><P>
Too little ram - max out your ram.