Hey i having a problem

While i was playing fallout 3 finding my dad after the enclave show up iwent in the next room then walk to the exit to find out

what is going on and it froze on me. even at the start it freezes.

I need help i cant take it anymore and i know im not the only one.

Here is my computer info

Manufacturer:

ACPI Uniprocessor PC
Processor:
ADM Athlon(tm)64 Processor 3500+
Memory:
1.00 GB of RAM
Hard Drive:
233 GB
Sound Card:
Realteck AC'97 Audio for VIA(R)
Speakers/Headphones:
JBL Pro
Keyboard:
Microsoft Natural PS/2
Mouse:
Logitech USB WheelMouse

Operating System:
CTX VL700