No. That's a problem I haven't come across in several years.
Firefox, Thunderbird, and Chrome all work the same in Linux as Windows, except for small things. Like Firefox's Settings are under the "Preferences" tab instead of "Tools".
The day may come when people running Linux have to worry about malware, but as of this date most Linux users don't run any anti-malware programs at all. Linux is more secure, but it's also largely about percentages. The bad guys aren't gonna waste time writing malware for the 2% of people running Linux when there's all those Windows users...
NEXT DAY EDIT: I should add that you can install Linux onto a 4 or 5 year old PC with decent specs and it'll run faster than it ever did with Windows. Downloading a copy of Mint or Fedora or Ubuntu is free, so you can revive a malware-plagued Windows box for the cost of a CD. A lot cheaper than the Apple you're looking at...