Welcome to LQ
If you have a specific qn, best to open a new thread for each one. See the Sticky notes.
In the meantime, have a read of the threads here in Newbie section, especially the many many(!) 'what's the best distro' threads.
Short answer; its up to you; there isn't a globally 'best' distro.
Here's a good site to see what's available www.distrowatch.com
Good cmd line intro and also explains a bit about how Linux works http://rute.2038bug.com/index.html.gz;
good background material, even if you think you'll never use cli.
A quick explanation of 'Linux is not (a free version) of MSwin' ; worth a read http://linux.oneandoneis2.org/LNW.htm
Do read LQ Rules www.linuxquestions.org/linux/rules.html