Ok, I'd say that since it's an eMachine that your issue with crashing is probably RAM related. I've had some friends who have purchased eMachines and they got nice fast CPUs but 256 to 350mb of RAM.
To give you a basis for camparison I am using an AMD 64bit Athlon at 2.2ghz with 1GB ram onboard and 1GB ram on my video card (nVidia chipset).
I'd say it's the RAM - there are a couple of ways to find out how much RAM you have (if you don't know) you can get there through 'My Computer' or you can do this
START>RUN>DXDIAG
That will give you a lot of good info on your machine.
I am willing to say I could be wrong (I've been wrong before) but right now I'd say your locking up is due to low memory. If that's the case the only thing you can do for now is to save, save often and when you do - make sure you do something like SAVE FILE-1 - then the next time you save SAVE FILE-2 - this way if your save gets corrupted you've still got SAVE FILE-1 to fall back on. I tend to do 3 to 4 saves on the same work.
I'll have something like '1701-OCT-A' and the '-B' and '-C' and so on.
It takes up some drive space but it keeps your hair in your head and not in your hands.
