If you only use it for your own stuff go with the advice given but if you trade with others with MS computers then Open Office has worked best for me. And yes it is a pig but a good pig. Most of the time I create documents for my own use, but for the few times I do create documents for others to see I simply give them the Oasis format, it is a standard after all.

Can't the Gnome office and Koffice both open MS formats? I ask this because I am much more likely to open MS documents than to give out documents to others.