I personally like Ubuntu its lean and it performs fine without any major issues. The latest 9.0.4 was released in April and it does support enhancements like 32 or 64 bit. Supports Open Office suite tools and provides automatic updates on them. The 9.0.4 also supports more Wi-Fi and 3G peripherals. Another neat feature is the windows migration tool that can be used to migrate many Windows systems over to Ubuntu. Or it can peacefully coexist in a dual boot environment as well with Windows.
Other features worth mentioning are CD/DVD authoring application like Brasero, Rhythmbox for a music player, Pidgin and Ekiga for video conferencing. The computer Janitor is also a neat program; it removes trash and older files according to the user’s specifications.
Additional info: www.ubuntu.com