MBP locks, thus force shutdown w/ Power button, then catastrophic app probs

Question

I have had two unexpected system lock ups which may be releated to low battery power, but have then caused catastrophic application problems. I do not want answers to the individual application problems here, I will refer to other Apple Support pages and forums for those. I'm interested in other users experience of the same catastrophic failures, if at all.
Event 1. (OSX 10.4.8)
I was using the MPB on battery and I knew the power was running low, afraid I can't remember how low but I'm sure it was below 10%. Without warning iPhoto crashed with an exception popup which said that it was related to low power - I didn't note the exact wording. The machine remained on, but I couldn't do anything with it, so I had to shut it down by holding down the power button.
When I next used it, it seemed much of the applications I had had running at the time had all got corrupted;
- iPhoto: my library was gone next time I opened it. All the photo files are still there but some complain they are corrupted when trying to view them. I'd been using iPhoto at the time and rotating a lot of photos. Photos loaded and rotated in that session seemed to have survivied, ones unrotated complain of corruption when I try to view them. Other threads have suggested I need to do a complete rebuild.
- Dashboard: my whole set up has gone and it has reverted to a vanilla original set up.
- Trackpad: my settings had all disappeared and I had to set it up from scratch again.
- Skype: It no longer remembered my login details. This I found interesting as it is not an Apple app.
Event 2. (After 10.4.9 upgrade)
The second time I had left the MBP plugged in and in sleep mode, so it should have been well charged. A friend unplugged it to use the socket. When I went to use it it was still asleep. It was asleep and unplugged no more than 24 hours but my experience is it can live like this for days, so it should not have drained all power.
I could wake it but I have a password set and the system would not register the key presses I made for the pwd in the pwd box. ie. no *'s appeared each time I typed. The MBP was working because as I tried to wake it by doing various key presses I obviously did something which made it play a track from my iTunes library which had been running when I last put it to sleep.
Eventually again I had to shut it down using the power button. This time when I started it up I had the following;
- iTunes: It said my library was corrupted and it had to rename it and set it aside and create a new one, all my Music is there but it looks like I will have to rebuild.
- Mail: When I started Mail this time it requested I set up a mail account as if it was the first time I had used it. It looks like most of my mail files still exist in my Library/Mail folder but I somehow need to recover the mail account.
- Messenger: my icon I used doesn't work and it has defaulted to the icon associated with my MBP account I log in with. I understand this could be because the image I used for my icon came from my iPhoto library and it doesn't take a copy.
I am half way through recalibrating my battery as suggested elsewhere in these forums. After this I will reset the PMU/SMC. However after days of trawling the forums I have yet to find anyone describes problems like these, so I have reluctantly decided to start a new thread to see if anyone has had similar experiences.
My MBP is 5 months old, bought at the London Apple Store in Nov 2006.
MacBook Pro 17" 2.33 GHz Intel Core 2 Duo   Mac OS X (10.4.9)   Memory 2 GB 667 Mhz DDR2 SDRAM
Intel MacBook Pro 17"   Mac OS X (10.4.9)  

Answer 1

I came to a similar conclusion after trying Disk Utility.  It said the disk needs to be reformatted.  Unfortunately, I've not been doing TimeMachine backups for 2-3 months due to problems I had with it.  one of those "I'll take care of that sometime soon" things where soon doesn't get here.
Right now I'm getting ready to hook up the backup drive and see what I can rescue.
Chuck