Mac help needed

Dave needs a hand.

He says...
"Well, I've been stymied. I call on the blogosphere for assistance here.

I bought and built a purple gumdrop iMac for my mom about 4 months ago. This was to upgrade her from an ancient wheezing G3 running OS9 that was driving me nuts to maintain. This was my first experience with OSX, and I found myself liking it an awful lot.

Now comes the problem. I upgraded the machine to > 512meg of RAM and a 40gig HD, and installed OSX 10.3 on it. It was running fine up until a few weeks ago.

Now we can't start the Finder. No desktop, no nothing. If we didn't have the dock, the machine would be useless. Nothing I've tried has fixed it - neither starting the Finder from the command line (sorry, don't remember the command we tried, but it resulted in a crash), nor running system update, nor running Repair Permissions. A reboot will return to the dock-without-finder. I've tried switching users, but the machine wedges when trying to get to the 'select user' screen.

I've tried moving the ~/Library/ tree out of the way and rebooting, no dice there either.

The last problem is... well, it's at my mothers house. So working on it has to be limited to the 2-3 hours I'm there a week visiting. I'll be there tonight (7pmish east coast time), and on IRC and AIM. If anyone wants to help me debug this, either drop a message here, or be around tonight while I'm at the machine. Let me know though so I can msg / mail / poke ya when I'm online again "

His contact info.

Update from Dave: Well, I did some work on it tonight. It think the only option that has a chance is to get media for 10.3.mumble and do an inplace upgrade. The machine is running 10.3.2 now, and nothing I've tried has cleared things up. I can't even run Disk Utility on it, since I don't have a finder or media. Ryan, thanks for the pointer, but I tried that as well. Even logged out and in as another user. I think we'll just need to do an in place upgrade to basically update most of the binaries in place.