I am not a tech guy and have been using Windows as these years. Recently thought to try Ubuntu as Micro$hit will stop XP support. I have few basic queries about Ubuntu which I guess more knowledgeable members can answer. 1. Now on download site there are 2 versions.. 12.04 and 13.10 Which one should I install? It says 12.04 will be supported till 2017 and 13.10 for nine months?! 2. Do I have to upgrade every time Ubuntu comes out with new versions? Ubuntu seems to be upgrading every now and then. It would be a pain to install an OS every nine months! 3. Will MS Office 2007 run on Ubuntu? 4. What about antivirus? Are there any free Ubuntu free antivirus? I did a basic googling about these queries... but either they were old/not relevant or have only confused me more. Thanks.