If you are annoyed with the eccentricities of the Unity user interface of Ubuntu, Linux Mint might be a good alternative for you.
The developers behind this project have just released the latest edition. Linux Mint 12 “Lisa” is now available as a free download.
As usual, the system requirements are pretty decent. It should work on most machines purchased in the last 5-6 years.
x86 processor (Linux Mint 64-bit requires a 64-bit processor. Linux Mint 32-bit works on both 32-bit and 64-bit processors).
512 MB RAM (1GB recommended for a comfortable usage).
5 GB of disk space
Graphics card capable of 800×600 resolution
CD/DVD drive or USB port
Read more about the new features here.