[Hampshire] Grub Error 17 and Filesystem Problems

Hello all,
I thought things seemed to be running a bit too smoothly...

In the last 2 days I have had problems booting. I'm running Kubuntu
6.10on an Acer Aspire 5633. One of 3 events would occur:
1. It would boot but after the KDE splash I would just get a white screen
and nothing would happen (no CAPS-lock light when I pushed the key so I
assume keyboard entry didn't work either)
2. It would boot but I'd get no sound
3. It would boot, I'd get sound, but I wouldn't be able to dial a PPP
connection

Occasionally I'd boot into a working system. However, on booting I'd get a
load of HEX numbers whizz by at the filesystem check stage and it would say
that errors were found but not corrected.
I could boot using the Recovery mode entry in GRUB and, after checking the
man pages several times I attempted to use fsck to fix what I assumed was a
filesystem error. I ran "fsck -a -A" thinking this would run through the
entries in fstab and automatically fix errors. I don't think this is what
it did.
Anyhow, I'm now presented with a system where, upon turning on the laptop
GRUB begins to load but stops with: Error 17.

Can anyone tell me what I've done and how I can fix it?

On the disk are the following partitions (as far as I can remember):
FAT32 ACERIMAGE (Acer backup image)
FAT32 WinXP MCE
ext3 /dev/sda5 /home
swap /dev/sda6 /swap
ext3 /dev/sda7 /

As always, I'd be incredibly grateful for any help you can give. I'd
really like not to have to reinstall everything as I was just getting
settled.

-Alasdair-