For those that haven't seen it... Mynameisnotlilly has a fantastic Youtube channel full of "Let's Play" videos, where he role plays Lilly in every game (including Fallout 1 & 2. Baldur's Gate 1 & 2, and Wasteland). In these games he role-plays Lilly's attitudes, and motives throughout his sessions.

*The Wasteland "Let's Play" is highly unusual... almost experimental theater in a way. Most people (including myself) would never play an RPG quite this way, but in my opinion it is really a fantastic way to play ~if highly impractical. I recommend watching the short 14 part Wasteland series on his channel, as a must see among the videos on Youtube.
http://www.youtube.com/user/mynameisnotlilly#p/c/74BAB66E726A508F/0/IvYcu5qaO-s

here check out my topic and see how people handle it differently
http://www.gamesas.com/index.php?/topic/1175362-your-characters-story/

I am not really big on the RP side of a game, I make a character and basically make him like me. All the decision I make and the way I fight in the game is all based on idea that if I was in this situation in real life, what would I do?

Draw a lot of inspiration from movies or books if you're stuck, another thing that can make it difficult is if you try to picture your character all at once,
try writing down some basic questions to yourself like for example:" What are his moral standings?"
And then you flesh it out with something like "why does he have these views on the world?" This spawns more questions and so on.
But first just get the basic idea of what kind of character you want to play, a concept and then think out reasons how he turned out like that and why, This builds the foundation for backstory and cool details.

In many PnP games you start by just filling out an archetype like "Thrill seeking gambler", "passionate tv-cook" or "vengeful gunman".

Adding mods that force you to sleep/eat every now and then can help. Personally, i just found them annoying as i'd either have to haul along a massive amount of food, or constantly go looking for food, but for some it really helps.
On a sidenote, as a bassplayer, i LOVE your sig. So true...

I think the advice to just pick a personality (preferably not your own), and make all your character's actions and decisions fit that personality, is the best advice for a new RPer.

Try and keep the personality fairly basic, not too many complications or subtleties - the people writing the dialogue options will have had just a handle of simple personality types in mind - and try not to get too obsessed with always picking the perfect dialogue choice. Sometimes the game writers simply won't have put in any suitable options for your character, only for the ones they thought of.

An example; one of my characters for playing Knights of the Old Republic was insecure, hiding that with aggressive responses in almost any situation. The only exception was with her trusted companions, who she tended to treat with sentimental indulgence most of the time - and vengeful fury if they betrayed her.

No backstory needed (that was provided by the game), but a distinct personality that led to some very good storytelling - she ended up stabbing one of my favourite NPCs in the back!

I got one tip for you.
You should give it time when you play an rpg. you might not get into the game at start.
I told my friend that and after a few hours of boring gameplay (according to him) he fell in love with rpg's. he plays it all the time.

Pretend that you were actaully born in Tamriel and grew up there. Do this in the context of your chosen race, since they all have different lifestyles.
Then start answering questions:
Why is my character in jail?
What did my character occupy himself/herself with before ending up in jail?
How did the character come to that occupation?

Do this backwards all the way to your character's childhood, and you'll have the backbone. Then add 1 to 3 "life turned upside down" moments where they seem to fit the most and work around them to make a coherent story. After that add any other tweaks necessary.