For a stable and slow Linux System

For a stable and slow Linux system-general Linux technology-Linux technology and application information, see the following for details. Ladies and gentlemen, let's say "Happy Dragon Boat Festival!" here first !!!"
Now, why do we want to find a stable and slow Linux system ??? It is actually very simple. Soon, I will leave my parents alone to go to other places to explore the world. I am still a little reluctant to stay at home... But you can't do it for your own sake of home and future...
Now I want to help you, younger brother. I have just been in this circle for a few months. I have not been very clear about the types of systems. Now I want to install a system for my parents, the requirements are not high. You only need to watch a movie on the webpage. Hope you guys can help me !!!
My existing configuration: AMD 3600 + X2
Onda N68PV Motherboard
KingboxDDR2 667 512MX2
Seagate 160 GB
Change the configuration after the Chinese New Year: Intel series low-end CPU
Intel G31 Motherboard
Western Digital 160G
KingMaxDDR2 667 512MX2
In the previous configuration, you have run Ubuntu8.10 and want to change the system so that your parents can learn it... Then install the following configuration after the Chinese New Year...
Thank you !!!