AMD graphic cards are the worse. Without proprietary firmware, you get
reduced functionalities. More and more code goes into such firmware. It is a
real problem. Next time you buy a computer, go for an integrated Intel
graphical chipset. Those perfectly work with Linux-libre, hence with any 100%
free GNU/Linux distribution such as Trisquel.
"Open source" and "free software" mainly differ on their values. It is an
important difference though and I invite you to read
https://www.gnu.org/philosophy/open-source-misses-the-point.html
Almost all licenses considered "free" by the FSF are considered "open source"
by the OSI. The Trisquel project sticks to the FSF definition and everything
in its repositories should be free (if not, it is considered a critical bug).
It is the best thing about Trisquel: you can enjoy your operating system
without fearing to install software that does not respect your freedom. This
is true as long as you do not install software from other sources (PPA for
instance). You can do so of course. But you then need to check by yourself
that the software is free and trust the source (no malware added, no
automatic update to proprietary software). SMplayer and mednafen are in
Trisquel's repositories. Go ahead and install them without fear!
Xfce is in the repository too. There is bug that prevents its install... but
there is a fix too: https://trisquel.info/issues/12680
The swap is an extension of the RAM. It is used when the RAM is full (and
because the disk is much slower than the RAM, you feel it badly). It is used
as well when you hibernate (the content of the RAM is dumped to the disk so
that it can be restored at reboot). If you use that functionality, setting as
much swap as you have RAM is a good idea. Otherwise you probably do not need
that. Otherwise, you may need no swap at all. You can take a look at the
current RAM consumption from the second tab of the "System monitor" (in the
"System settings"). Try to run many applications (LibreOffice + Abrowser with
a lot of Web pages opened, an HD movie in Totem, etc.) to get an idea of
whether you are close to swapping.
