Basics:
1. Privacy and Security - Applications/Settings/Search Engines - chkrootkit (checks for rootkits), turn all computer use tracking off in Privacy Settings, Firefox, IceWeasel, Opera 12.16 Browsers, default search engine DuckDuckGo - but NOT DuckDuckGo Plus as this negates DuckDuckGo 'raison detre'!, clamav - free AV Scanner - if you want to be totally secure then get Tails with TOR!
2. LibreOffice - full Office Suite - and streets ahead of OpenOffice - as most of the latters devs left for The Document Foundation.
3. Sylpheed/Claws Mail - Full synchronisation on and off-line with appropriate plugin.
4. Specialist:
Photography: GIMP, Dark Table, Digikam (latter based on feedback from forum members)
Video Editing: Easy use: OpenShot, Pitivi - advanced Cinelerra, KDEnlive, LiVES
5. Addictive Games: Rise of the Blocks - cool background music that I will use in future videos!
GAV - the original - (Gnome Arcade Volleyball)
TORCS used to be the best racing game but is called something else now and not compatible - shame!
There was a good program written by a Dutch programmer - 'Driver' - I managed to compile the demo on Open SuSE 9.3 Pro - it had a BMW Coupe and 'VERY' realistic! (The Windows demo version was on a cover disc of PC Format with neat customisation of paintwork, suspension etc but the demo only had a VW Polo to play with!
The lighting was incredible!
Pingus, SuperTux, TuxCart.
Well that's about it - for now!
5. Audio Player: Clementine with ProjectM visualisation/Kaffeine with Goom Visualisation Plugin
6. Media Player: SM Player (with SM Tube!), Kaffeine
7. Emulation: Wine - if resources can stretch to it - CrossOver from Codeweavers.
i'll figure it out 
but what would you recament ?