Recs.
Updated
Requires 64mb RAM, can be installed with a small footprint, and includes several lightweight desktops to choose from.
Since its first beta release in April of 1993, the Slackware Linux Project has aimed at producing the most "UNIX-like" Linux distribution out there. Slackware complies with the published Linux standards, such as the Linux File System Standard. We have always considered simplicity and stability paramount, and as a result Slackware has become one of the most popular, stable, and friendly distributions available.
SpecsUpdate
Pros

Cons
Con Not for beginners
Installing Slackware may be difficult to those that are not intimately knowledgeable about Linux and its inner workings. While the commands necessary to install may be simple to a Linux user, someone who has never used Linux would have no idea on what to do and would be forced to find a guide.
Recommendations
Comments
See Product Page for "Slackware"Built By the Slant team
Lustre recommends the best products at their lowest prices – right on Amazon.