For some reason, I cannot bring up the applications menu on my daughter's computer. I am suspecting that the she has filled up her hard drive - downloads everything, never deletes anything, no concept of filling her drive. The mac boots up, albeit slowly, but once it comes up, we cannot access the applications menu or anything else such that I can start the deletion process.
If you can get as far as the trash can, try there first.
Outside of that, there might be some things you can try, such as connecting the HD to another Mac, and seeing if you can get at it that way. It MIGHT be worth a trip to the Apple Store.
presuming that safe mode does not work, how would you set up the firewire and other Mac? (This is mostly my curiosity here--) What does one do to get the balky Mac HD to show up on another unit?
Provided the hardware in the cranky machine is ok, here's how things work:
1) Shut down both machines
2) Connect the machines using a Firewire cable
3) Boot up the good machine and log in.
4) Once the good machine is finished booting/logging in, start up the other Mac with the T key held down
5) This Mac's hard drive should show up on the good Mac as an external hard drive (probably with the Firewire symbol)
From here, you can try deleting files, but that may not work due to permissions issues. You can definitely check how much space is free on the drive and you may also use Disk Utility (Applications>Utilities) to repair the drive.
Disk Utility should only be used if the OS version are the same--ie: the working Mac is running 10.5 (Leopard) and the stuck one is also running Leopard. If the two machines are running different OS's, do not use Disk Utility.