Hey there! First off I wanted to say thank you for being an open minded player who genuinely seems to want to improve and learn rather than just bitch & moan about X Champion being OP. Given the overall tone of the community at large, I think finding someone as earnest sounding as you, as a relatively new player, is a freakin' diamond in the rough. So keep up the good attitude! Really, whether you win or lose, if you're fun to play with, you and everyone on your team will have a better time. Your friends will be more willing to help you learn if you're willing to take criticism and feedback, and you'll make more friends while playing if they find you're a pleasant person to play with.
Second, for context, I'm not a pro level challenger player or anything. I just don't have the time to commit, especially with all the recent changes and reworks (and my computer died a while ago x.x) However I've been playing League since its Beta, and I keep up on the patch notes and general discussions and red posts as best I can.
Enough for introductions. On to your post!
Don't Lose Before The Game Begins
Before anything else, remember not to put too much heart into any one game. There are a lot of factors here that are either out of your control entirely (how good your team is at communicating, pinging, and coordinating plays) and others that will simply take time to learn (understanding the nuances of Champion mechanics, understanding match ups). Its like poker - professional poker players have plenty of games they downright lose from the opening hand, but they don't care. Instead, they look at the long term - playing hundreds if not thousands of games and then looking at the averages and end results. So you have a bad match up? Learn what you can, and then move on, but don't assume that you'll always lose that match up every time. On the other hand, don't assume that just because something works once, it'll always work. In the end, Player Skill can still trump Champion Select.
For example a few months ago I was experimenting with Top Yasuo. He had received some tweaks to his shield and I was actually having pretty good luck against tankier tops by going with an early zeal>BF>PD build path. I went up against a Darius and wasn't sure how I was going to do. But it turns out he was having a bad game, and I wrecked him. I kicked him up and down the lane until he chose to camp mid instead. A few games later, I get another Darius. "Pfft", I figure, "I got dis." This time, I got destroyed so hard my jungle gave up on me. Because that was a good Darius player. So don't think that just because you lose once that you'll always lose.
If you end up on the poor end of a match up, then you'll have a harder hill to climb, but its still possible. It just might require that you really focus or ask for early ganks or play a lot safer than you normally would.
Back To Basics
Last Hitting
Once you've gotten yourself into the mindset that a single game does not define you as a player or a person, then start working on your fundamentals. Learn to last hit. How? When you're in lane (even if you have to go to a Bot game or practice game), attack a Minion and see how much damage you do, watch the actual number. Then, click the minion and wait for his health to reach that point. Then try timing your hit - watch his health dropping from the other minions. There is actually a pretty reliable rhythm of the minions attacking and you'll be able to predict exactly when it'll drop below that "kill threshold". Try to hit him exactly when you'll be able to last hit it. Then eventually you'll be able to predict this intuitively based on the health bars and you'll be able to stand in the middle of a wave and be able to pick them off easily.
Every Champion will have a different last hit rhythm, especially early on when you don't deal as much damage. The attack speed, attack animation, and base AD values will be a little different across the board. Some Champions (Nasus) make it easier by having an ability designed for farming. Others like most mages are more difficult because of their naturally weak Auto Attacks. Singed is kind of interesting - if you're not careful, the timed ticks of your poison can actually miss getting a few last hits by minions that are in the middle of a wave, but once you stack up some damage on it you'll be able to farm entire waves at a time.
Towers
Related to last hitting, also get an idea for how many tower shots it takes to kill a Melee Minion, a Caster Minion, and a Cannon Minion. Sometimes you'll watch a tower hit a minion, you'll hit it but not quite kill it, and then the tower will kill it. In this case, you need to hit it once, let the tower almost kill it, then last hit yourself. So get used to that pattern as well and it'll be a lot easier to farm under your tower.
Similarly, get used to towers in general. Memorize their exact aggro-range. Use it your advantage. If you're Singed and you're getting pushed back to your tower, see if you can bait your enemy into harassing you close to that tower range. If you can time it so that a minion hasn't yet entered your tower's range because the wave is pushed just outside it, you can Fling your enemy into your own tower and force them to take a hit or two.
On the topic of Singed, you can use his poison within the enemy tower range - it won't aggro until they actually take damage from it. So if you are pushed up to their tower and they hang back behind their minions, you can step into the tower's range, drop a trail of poison in front of yours, and step out of range. It can help to pressure your enemy off the wave, so they lose CS if the tower takes the minions. And if they step forward, they'll take damage from your poison, but you've already moved out of range so you'll be safe. On the flip side, be careful not to walk back into range while the enemy is still taking damage, since it'll aggro the tower onto you.
Alright, that's enough for now, this is just a few things to think about as far as working on your basics in lane. Just keep up the good attitude and keep playing.
As for if you should play Ranked: if you can play it without getting totally down on yourself, then go for it! You'll get better, faster, if you play against people who are probably trying a little harder or less likely to goof around then they will in normals. Ranked will encourage you to really hone those basic skills. Just don't sweat it if your Rank is low for a while. Rome wasn't built in a day, and neither are professional teams.
Singed before ranked, now I am questioning my reasoning behind that statement after being crushed by a 
Nasus; I 
Garen, the enemy laner then chose 
Darius and BM'ed me in All Chat as I was destroyed. Being in normals, I have not been so badly stomped before. I admit that I am not the best at last hitting and I have had little exp. with farming under tower as not being acquainted to having to camp underneath it, is there any advice that someone could give to a scrub in need? should I continue with ranked since it seems like the only place I am forced to focus on overall improvement of my game play, instead of normals where I seem to neglect it b/c I still do relatively well? Any other general advice? The current roles I 
