Depending on optical hardware to a certain extent, but it is wise to burn CDs at the slowest speed the drive will allow.
At minimum, first do a media check on the CD, to ensure it has burned reasonably well.
I doubt it matters which version of PCLOS you install, provided of course you get a good install.
Install what is most comfortable for you to work with.
I use KDE so am not very up to the mark with the means of achieveing things in Gnome.
Don't let that influence you.
You will get a smaller install by using the ISO of preference rather than using a meta package after you install what you do not wish to use.
While running it is useful to have "top" running in a terminal, to see what is using the most resources.
It also will show if there might be a Zombie running at the time of a failure ..... a reboot fixes that.
You should be able to install in a few minutes and see how things go ... whichever ISO you use.
To change the install will only take a few more minutes for a fresh install.
Whatever you decide should be OK, provided the ISO has checked out against the MD5sum and the media has passed the media test.