Linux is not (yet) vulnerable to malware because no-one has bothered to write any. It's vulnerable to weak passwords on SSH login and things like SQL injection on servers, plus the odd privilege escalation exploit if someone gets a user password. So desktops are pretty safe - you won't yet get infected from email or browsing. Adobe software has had vulnerabilities, but all the payloads hackers write are targetted at Windows so they won't run.
Most people are getting Ubuntu or Mint for desktops. Just get the latest production release which should support newer hardware. There is the latest Firefox (same as for Windows), plus Chrome, Flash plugin (either the latest, or nearly so), Adobe Reader (ditto), OpenOffice, Thunderbird, etc. which covers basic browsing/email/office stuff, then there are video players either built-in or available for download etc.
The games selection, however, is lousy, though there was Doom and Quake
