Just for Info - I recently purchased Tesco Complete Office for just under £20 at a local Tesco Store. Having just installed it and taken a look around this seems to be a very cheap and good alternative to the Microsoft products.
Complete Office contains all these programs which are fully compatible with the MS products:
Draw
Photo Album
Presentation (like MS Powerpoint - the only thing I could not find on it was the ability to print handouts, but I can live without that!)
Write (a word processing facility)
Database (for storing documents)
Spreadsheet
From what I have seen so far, all the programs are very user friendly and have plenty of features. Installation was simple.
It was really only the Presentation program that I was after, but purchasing this package was far cheaper than buying just MS Powerpoint! The package allows you to install it twice, so you can have it on your main computer and a laptop for instance!
If anyone is looking for such a package at reasonable cost, I can thoroughly recommend it!