Ubuntu can be the perfect operating system for computers which are five or more years old, and are still in good condition.
Nearly all versions of Ubuntu Linux like 8.04, 9.10 10.10, 11.04, etc can run very well on a computer with a 1GHz CPU/Processor, 512MB of RAM/Memory, CD-ROM drive, 5GB free hard drive space, a basic video and sound card.
Many older computers built in the last 5 years are powerful enough to run Ubuntu Linux without to perform any major upgrades like a new CPU. In some cases, you may need to upgrade to more memory, so Ubuntu runs more smoothly, and is better at multi-tasking. Unfortunately, not all video cards and sound cards work with Ubuntu Linux, but if you use a popular brand of video card like ATI, Nvidia, or Intel onboard graphics. Ubuntu would probably work on your computer in my experience. Realtek, and C-Media sound cards also work with Ubuntu in my experience. Nearly all computers built-in the last 10 years probably have 5GB of free space to install Ubuntu onto. If you do not need to save your work, you can just run Ubuntu from the Live install CD which is in your CD-ROM or DVD-ROM drive. You can save your work to a USB flash drive. Ubuntu Linux is one of the few popular operating system which you can run from a CD-ROM drive, and don’t even need a hard drive to run off of.
In my experience, Ubuntu Linux works great as an everyday operating system on my older 1.8GHz computer with only 1GB of RAM, onboard video, and sound. I mostly use Ubuntu Linux 11.04 for office work, browsing the web, checking e-mail, watching videos, listening to music, chatting, playing games, web design, and doing minor video and photo editing. Ubuntu Linux has never failed me when doing the tasks which I listed above.
The thing I enjoy most about using Ubuntu Linux on my older computer is it is stable, fast, secure, and easy to use after installing it on my computer. Unlike other operating systems I used like Windows, I do not have to adjust any of the settings for good performance, and stability. I notice my web browser, media players, and office suite crash less when I am using it in Ubuntu Linux compared to Windows.
The System Requirements for Ubuntu 11.04 Desktop edition are 1GHz CPU, 384MBs RAM, 5GB hard drive, and a monitor resolution of 1024×768 pixels. Ubuntu Linux 11.04 system requirements are very fair for a modern operating system with so many features and options for you to use to improve your computer experience.