OpenOffice is lovely - it does practically everything that M$ Office does - and includes Writer (word processor), Impress (presentations - like Powerpoint), Math (mathematical function creator), Draw (vector drawing tool), Calc (spreadsheet), Base (database) - and without the hefty price-tag - it's open-source and free. And it's compatible with Office and such like. I've used it for over 6 months on my laptop now with no problems (I wasn't about to shell out for another M$ licence for it so my laptop's largely an open source zone).
What is doesn't come with though is templates like M$ Office does - here though are sources of templates for OpenOffice: