All the suggestions seem to be on the mark. BIgG's advice about blowing the crud out with gunscrubber is a whole lot easier than removing the side plate. It will do the job well enough for most people. Remove the grips and cock the hammer then squirt the stuff in an let it dry and then finish it off by squirting a LITTLE Rem Oil or some such stuff. This is NO WAY the best cleaning advice, but for once in a "blue moon" it don't hurt..
About the front screw just ahead of the trigger on the right side of the S&W, This is called the yoke screw and it holds the yoke and cylinder in place. There are no springs under it, unlike some ofther revolvers so it is easy to remove and put back. You just need a good screw driver that has a blade that won't slip and MUST BE NARROWER than the slot in the screw or you'll scratch the gun for sure. I use a Chapman set, but also have a one dollar screw driver that I filed down just to fit the yoke screw, since I use it so much. S&W will sell you a real beauty one if you ask nice with a credit card. They used to be included free when you bought a gun, but those days are long past I believe.
THE GREAT Revolver book is "The S&W REVOLVER - A shop Manual" By Jerry Kuhnhausen. There are no words to describe how wonderful this book is. It is only $20 new, you may find it on the internet "used" for less. This book will answer all your questions and a whole lot more. He also has a couple of beauties on the 1911, if you like them bottom feeders.
Elliot