Powerbook G4 is really hot and doesn't turn on

It just started getting really hot quickly for about a week before it didn't turn on. I would have it tilted so that its not flat, hoping that it would give it more air but it didn't do anything. I don't even need to do much to get it really hot. And I shut it off every night, so it should get to reset itself. I haven't done anything different that I haven't before. Any fixes please!? Also what's really weird is that it gets hotter and hotter even when it is off and not even plugged in.

It sounds like a battery fault then. It could be constantly powering until it's drained. You need to try a new battery and hope that the board isn't fried.
What happens when you try and turn it on?
When it was working did the fans cut in or run continually?

Well now I changed the battery, luckily I had an extra, and it doesn't get hot anymore. But now after just a few minutes of use it gives you that screen saying to hold the power button restart it. You know the menu, it has it in all those different languages too. And also I have to take out the battery and put it back in to power it on. And as for the fans, it seems like during the week that it was getting hot, I don't remember them coming on at all.

Ok, that's a start.
Run Disk utility from you install discs and verify/repair the HD to see what comes up.
It looks likely that you will have to do a clean install of the OS, but we won't go that far yet.

Now I can only get it to actually turn on sometimes. Sometimes when I press the on button it just makes noise from inside the computer, like it normally does when you turn it on, but the screen stays black. But if I let it sit for awhile it will turn on. But it still doesn't last long before it freezes. Now I'm trying to boot into safe mode but it just stays at the beginning grey screen with the apple and spinning dial thing. I know safe mode takes awhile, but I let it sit for a half hour and still nothing different. Also I don't have the install disks, but I do have a macbook pro that I could use from a friend. Maybe I can boot it from there and try to do some repairing.

Well thanks a lot for your help! It seems that the battery may have been a big part in the problem. Once I switched batteries, it wasn't hot anymore. Then I did some looking around and performed the single user boot, and with the fsck code it fixed the problem. I'm really happy right now, and thanks again for all of your help. Hey do you have any suggestions on how to keep it cool? I know not to put it on soft surfaces, I'm thinking software like G4 fan control (but don't know how to use it), or maybe even a cooling pad.:

Well done. I would have suggested fsck to you as you don't have discs.
Yes, a cooling pad will help, but you need to make sure the fans kick in at the right time too, because if they aren't working you could be back to square one, so try running it on a table or hard surface for a while.
Get this:

Temperature Monitor 4.7 software download - Mac OS X - VersionTracker

And install it, very useful to keep an eye on things.