Zencafe is the best and the first Linux solution that suitable for internet cafe.

Zencafe GNU/Linux is a desktop Linux distribution designed specifically for public Internet cafés.

Based on Slackware and Zenwalk Linux, it includes auto-recovery features, Internet café billing and management software, and other graphical system administration tools.

Zencafe's default edition uses Xfce as the main desktop, while its "Lite" edition, designed for older or less powerful computers, installs the IceWM window manager.

Updates (via Distrowatch):

Zencafe GNU/Linux is a Slackware and Zenwalk-based distribution designed specifically for deployment in Internet cafés. The project's latest release, version 2.2, was announced earlier today: "This Zencafe version uses the latest Zenwalk Linux distribution and kernel 2.6.33.4. Mainly designed for use in Internet cafés, Zencafe is polished and easy enough to be operated even by a non-technical user. With the included auto-recovery and Internet café management software, Zencafe is the first Linux solution that is suitable for use in Internet cafés. Software included: Linux kernel 2.6.33.4, OpenOffice.org 3.2.1, Mozilla Firefox, Pidgin and Gyachi (instant messengers), Mkahawa Internet café management software, auto-recovery and kiosk mode protection. What's new? Simple installation process, user-friendly keyboard shortcuts, additional applications...."

Here is the full release announcement.

Download: zencafe-2.2.iso (595MB, MD5).