Office Software
For the price, you cannot do better than Libre Office 4 (for WP/SS/DB/Presentation) and Thunderbird for mail. The only real glitch I have had with Libre Office is that I can't get it to cope with forms created in MSWord.
Thunderbird is excellent for mail, although it doesn't have the same integration with a calendar that Outlook does. Try them before committing yourself to £70 per year!
For the occasional document that needs to be shared, would a free Dropbox account suffice?