Compaq EVO d512, WinXP Pro, normal factory machine from there.

I'm trying to help a friend up north fix her problem.
Started as: Son using her machine did a bunch 'o downloads, disk cleanup, and defrag last week. When she got back to PC for her own needs - her address book and a bunch of data is missing.

So, rather than resort to all kinda software to undelete or whatever.....thought we could go back to earlier date/Feb. when her stuff was last seen by her....and System Restore.
First: I had her run a couple different antivirus (Housecall, AVG), no severe threats found.
Next: She was trying to (normal mode) run SR and each date gave the can't do, have been no changes error, and one error said software distribution point - also would/could not restore to that point.
Next: ok. let's try getting into safe mode, disable avg for the moment, and try sys rest. there. She says she can't make it go into safe mode. Keeps booting normally, as if F8 is not even being pressed at all.

I'm stuck in stupid right now, trying to think what we can attempt next.

Any suggestions ??
Thank you

If her son clicked the wrong button in disk cleanup it may have erased her backup restoration files. What type of data was missing?

address book primary concern she has. Major headache to recreate.
Says she can FIND the "folder" and sub-folders - but Empty.
Yes, I'm aware if he hit advanced and auth. for it to clean restores' they are chucked. lol
Thanks. All ideas welcome. She is having trouble making it go into safe mode.....can't seem to catch F8 & the Compaq logo to coincide. I'm looking for work around for that too. But I'm long distance (Southern Quebec and Pgh.,PA).....and she's NOT familiar with ANYthing DOS command related or I will Never send her there alone !!!
Least we got the virus issue tended first. That's a 5star OK !! part of getting down the list on this stuff.

Also.....I'm dealing with a lady who had no idea how important it is to "Backup" !! Now, learning bone-deep that that's gonna be the very first thing IF we FIND that !!!!

Technician's mantra: Backup , backup.....

address book... in what.. outlook, or outlook express... and what version... 2000, 2003

To Boot Into Safe Mode:

1) Start-Run type msconfig
2) Go to Boot.ini
3) Check the /SAFEBOOT checkbox
4) Restart

Sounds to me like someone needed some extra disk space for downloads, and deleted what to him seemed like unnecessary files.

Going back to an earlier system date won't undelete files. And if the disk space was used for other purposes in the meantime (downloads and defrag will both do that), the files are permanently gone.

Where's the backup disk of the files? Oh, let me guess... There's no backup.

Lesson learned: Make backups.