Currently as of 18/05/2013 There are no reported viruses on the official Second Life website. Although it is not impossible for any website to become infected with a virus, Second Life is considered to be a safe site.
I have personally been a Second Life resident since 2006 and have never encountered a virus.
The Official Second Life viewer is not known to contain any viruses.
It is possible to simulate pregnancy in Second Life, also possible in InWorldz and Avination
Yes, it is possible to simulate a pregnancy and birth of a baby within Second Life.
It is possible to stream videos within Second Life and view them directly or display them on a prim.
Since viruses are not alive they can not have life processes.
The official Second Life viewer released by Linden Lab and the official Second Life website do not contain any known viruses. It has been reported that third party viewers in the past have caused security risks however these are no longer in use.
Yes, it is possible to feed people or avatars within Second Life using scripted food and animations.
As far as I know .... There is no possible way play Second Life without downloading a viewer
No Rhapsody itself does not have viruses. However it is possible that the ads that display on Rhapsody may cause viruses.
Yes it is possible to have babies on Second Life, there are many HUD's available that will simulate pregnancy and prim babies can be delivered by maternity clinics. Adoption is also available within Second Life.
The Phoenix viewer no longer supports Second Life, as a result of this it is not possible to log in world using this software.
No. Second Life (SL) is completely safe, if you download directly. There are alternate SL Viewers that are user created that can be used in place of the official one referenced above. Those could contain viruses. As a normal precaution: Make sure to run any program (executable) files through a virus scanner before installing.