There are more ants in this world than humans, this does not mean they are superior to us. There are more windows systems than Ubuntu Linux, this does not mean Windows is superior to Ubuntu.
Linux users swore that 10.10 version of Ubuntu will be superior than Windows and it has done it. It has done it in style. It has done so well that I think it has overtaken even the invincible Apple. Apple may be leading because it has got very tight integration of software and hardware.
The Ubuntu user interface has got really slick, and looks far better than Windows 7. Right from 2006 Ubuntu has been more stable than Windows. Ubuntu is faster and blazes even in 2 GB RAM, occupies less installation space, there are many (in-fact thousands) of free applications available in Ubuntu ready to be installed.
Ubuntu comes with office productivity suite like OpenOffice preinstalled in it. This OpenOffice can read and work with Microsoft office files and can also save your documents to a better format called the open document format (which is used by many governments world wide).
Ubuntu has a built in movie player, a music organizer and player called Rythmbox which integrates cleanly with UbuntuOne music store from where you could buy music.
There is a bittorrent client Transmission which enables you to share files using bittorrent trackers like thepiratebay.org . And not to mention Firefox, the worlds best browser comes packaged with Ubuntu. Its far superior and safer than Internet Explorer than runs on Windows.
If you are a programmer you can use Python programming language to quickly write programs and use Glade interface designer to construct GUI. If you are a Microsoft guy/gal and miss that IDE thing, you can opt for Mono and Mono Develop which a free .Net implementation.
Web programmers can install PHP, Apache and MySQL and can start rocking with it. Ruby 1.9.2 and Ruby on Rails 3.0 is not supported out of the box, but if you google it you can get lot of help about it.
Whats not good
UbuntuOne a cloud storage for files offered by Ubuntu is not working upto its expectation. I have installed Dropbox which gives same amount of storage and works really well with Ubuntu.
Ubuntu and its updates will always be free no matter what. Use can use it for any purpose. If you feel like contributing you can. Its not like Microsoft which craves for your wallet.
A better system
You must have noted that I haven’t told about virus scanner on Ubuntu. Well, Linux is really stable and since its updated and get huge contributions from programmers around the planet, most of its security flaws are fixed really fast and you are very safe with it.
So if you are a windows user, goto http://ubuntu.com and give it a try.