Porteus

New to Linux, I'm planning to run it from a usb drive. On the download page there are several options : Cinnamon, KDE, XFCE, and Mate looks something like following :

[ ] Porteus-CINNAMON-v3.2.2-x86_64.iso 23-Dec-2016 23:59 272M
[ ] Porteus-KDE-v3.2.2-x86_64.iso 24-Dec-2016 00:09 413M

So which one should i use?

You can try all desktop environments, but 1st meeting with Cinnamon for newbies - it's better way.

Cheers

It depends on the power of your computer. If you have a relatively recent linux box, you could appreciate runnin KDE. For older boxes xfce is my favorite. You will find help with the different desktops easily and swiftly and once porteus is installed you will be able to change DE almost instantly almost without any efforts. You will have less problems if you use linux file systems: ext2, 3 or 4 to partition your usb key.

If new to Linux best off starting with Cinnamon, I would say.

From the lightest to the heaviest:

1- Xfce
2- Mate
3- Cinnamon
4- KDE

I prefer Xfce among these 4, but I actually use LXQt because it's even lighter than Xfce: LXQt 0.11.1 x64