Moblin is just an Intel distribution of Linux (based on Fedora), although it's one that benefits from some unique tweaks and a newly designed user-interface. Moblin is based on the familiar GNOME/GTK desktop, like distros such as Ubuntu, but this is largely invisible because of the UI improvements.
This tutorial shows how you can set up an OpenSUSE 11.4 desktop that is a full-fledged replacement for a Windows desktop, i.e. that has all the software that people need to do the things they do on their Windows desktops. The advantages are clear: you get a secure system without DRM restrictions that works even on old hardware, and the best thing is: all software comes free of charge.
LibreOffice is the free power-packed Open Source personal productivity suite for Windows, Macintosh and Linux, that gives you six feature-rich applications for all your document production and data processing needs: Writer, Calc, Impress, Draw, Math and Base.
Ubuntu comes with a LiveCD installer. You can run the operating system without changing or formatting your hard drive. I can say it's pretty awesome because there are other things you can do aside from installing the OS. I will tell you that it can even reset your windows administrator passwords.