Just as many of FLOSS users, I too suggest Free (as in freedom) programs to my friends. One of the largest projects (aside from #linux) is #libreoffice. Now, they are all used to MS Office and when I showed them LO, they didn't wanted to learn a new interface and ended up not switching. BUT I have recently found out about the option in LO to change the interface to more MSOffice-like and I think it will make it easier for new users to switch.

View > User Interface > Tabbed