So on my Windows 7 install, I've got multiple free malware/virus scanners and a firewall up. But I've heard that Ubuntu (or Linux in general) is much more secure by default.
So what additional security measures should I take, other than the obvious precautionary measures (aka avoiding shady PPAs)? Should I install a lightweight firewall or something of the sort? Or is the security I get with Ubuntu out-of-box going to be enough for daily web-browsing? I'd rather not have to install too much software, I'd like to keep this PC running as fast and light-weight as possible.
Also, if I should have the misfortune of getting my Linux install completely messed up (say, I install a malicious software package), is there any way I can prevent this digital fire from spreading to my Windows partition?
In general, I'm just trying to find out whether or not I can just jump into cyberspace with nothing but common sense and Linux's built-in protections to safeguard me.