Help -- System Won't Start After Disabling System

In order to resolve slow speed disk issues, Symantec advised that I disable System Restore. After I restarted, I get a black screen with "Invalid System Disk. Replace the disk and press any key." What do I do here?

Duties are not performed for duty's sake, but because their neglect would make the man uncomfortable. A man performs but one duty - the duty of contenting his spirit, the duty of making himself agreeable to himself.
Mark Twain

I am running XP Pro and have system restore disabled and all is fine.
The only products of norton I have is Antivirus Corp 8.1 and live update. I have used all of their products in the past and since upgrading to xp have found them to make my xp pro system very buggy!
Speed disk is the worst with XP, give diskeeper a try, executive software is the developer and they made the base for xp's defrag.
Hope this helps,
Steve

IMO the best is PerfectDisk 6.0 by Raxco.

I'm running win me by the way...

I'm currently running dell's diagnostics disks (taking forever!). This will supposedly take care of the issue.
Disabling System Restore in win me is apparently a no-no; those Norton douchebags should have known that.
Yeah, I've got diskeeper and it's worked well for me in the past, although lately, the percentage of free/defragmented space doesn't change at all after defragmentations...I wonder if it has to do with how full my drives are (C: 700mb/7gigs is free, D: 1.5 gigs/28.5 gigs)
I'll give that other defrag program a try, too.

Slightly off the subject, but while I was on the phone with dell, they told me that not only will I no longer get support if I upgrade from win me to xp pro (like I was planning to) but that I would run into compatibility issues. Is installing xp and office xp worth not having round-the-clock support (which is vital for a newbie)?
Anyone made the successful switch without problems?

Duties are not performed for duty's sake, but because their neglect would make the man uncomfortable. A man performs but one duty - the duty of contenting his spirit, the duty of making himself agreeable to himself.
Mark Twain

You make a good point about needing a minimum percentage of space free in order to have a proper defrag.

The latest on the "invalid system disk" error: Yup, I'm screwed...:swear:
The norton boot disks, dell diagnostic disks, and a dirty reinstall of win me all did nothing, and they're telling me I have to just reinstall my os completely now (my xp pro and office xp folders courtesy of kazaa are sitting on my c drive, by the way)

I'm told I can bring my harddrive to a local comp usa or repair center and that they might be able to save some of the files and documents I need, but that will be pricy...

Just want to double check with you knowlegeable techies: am I out of options here, or is there anything else I can try before reformatting?

Duties are not performed for duty's sake, but because their neglect would make the man uncomfortable. A man performs but one duty - the duty of contenting his spirit, the duty of making himself agreeable to himself.
Mark Twain