Help me figure out what sets these minifigs belong to!
Numbering your minifigures 1 to 19 by going from left to right, top row first, I see the following:


gen035 - Skeleton with Round Brick Head (Ninjago Bowling Pin) from set 2519 Skeleton Bowling.

Same as 1
Same as 1
oct027 - Octan - Racing, Blue Legs, Blue Helmet 4 Stars &amp; Strips, Trans-Light Blue Visor from set 9293 Community Workers. Note that the minifig head in this figure is not correct in your image - it was likely swapped out by the previous owner.

The torso is 973pb0510 - Torso SW Armor Clone Trooper Pattern (Clone Wars). There are several minifigs that have this torso, including 8 with white arms and black hands. A full list is located here: https://www.bricklink.com/catalogItemIn.asp?P=973pb0510&amp;in=M
Not LEGO.
Not LEGO.
Torso is 973px83 Torso SW Dark Gray Shirt, Belt with Red Buckle Pattern (Padme), which belongs to sw025 Padme Naberrie from one of two sets from 1999: 7131 - Anakin's Podracer or 7171 - Mos Espa Podrace. Note that the arms must have been swapped out by the previous owner as the original minifig had blue arms. 

Either njo007 Kai (missing his headscarf) or njo052 Kendo Kai (missing his Kendo gear). Appear in 7 sets from 2011/2012.
sw258 - Hoth Officer (with another minifig's head on top). From set 8083 Rebel Trooper Battle Pack.

cc4066 Actor 1. From polybag 4066 - Actor 1, released in 2001.

njo013 - Lord Garmadon (Ninjago). Could also be one of 2 other Lord Garmadon minifigs (with different gear). Part of several Ninjago sets from 2011.
Not LEGO.
Not LEGO.
Not LEGO
sw401 Imperial AT-ST Driver from set 9679 - AT-ST &amp; Endor.

The torso is 973pb0318c01 Torso Speed Racer Pullover Open Collar, Diagonal Wrinkles Pattern / Blue Arms / Light Flesh Hands from the Speed Racers theme. The legs do not belong to this torso. Torso belongs to sr001 Speed Racer, Blue Pullover from set 8158 - Speed Racer &amp; Snake Oiler from 2008.

Another likely Castle related torso that I haven't been able to identify yet. Seems to have a sticker on it.
Thanks to Samuel L.(!), this torso is 973px67c01 Torso Police Vest, White Shirt, ID, Yellow Star Badge Pattern / White Arms / Yellow Hands. It was part of 11 minifigures in the Classic Town theme, and those minifigures appeared in 18 sets.