Those verses warn people, not force them to become Muslim. If you don't believe them, then that's completely fine. Though fear of hell is a driven element of religion, it also governs ethics. Fear of punishment leads me to not steal or kill. I fear a punishment from my creator, therefore I refrain from unethical practices.
Say you shot and killed 3 innocent people, do you think when you die that everything will end in a snap? Or the spirit will be reunited with the Universe? Etc...? Etc...? We are in a physical reality with tangible evidence of creation, it's all around us. A man who kills men for a living and claiming it is okay to do so will later realize it harms more people than it does benefit. Sadness, fear, guilt and other feelings are intangible, but influence our reality and our energy. Our energy channelling determines our psychology of reality. For example: A fat ass who watches the Superbowl, loves fox news, hates Muslims, verbally fights people if they do not agree with them, whole-heartedly says there is no God, without presenting any evidence to finalize the claim, etc... is exposed to the environment of negativity and close-mindedness. That same person can pick up the books he criticizes and examine all sources before making arbitrary claims.
Thanks to Islam I show everyone respect, though I'm not perfect, I am aware I need to struggle to stop sins that can be avoided. I've been harassed by a jinn for 2 years because I started hating my faith due to being influenced by horse shit like Call of Duty and Mainstream news. Whether it's real to many and false to others, this is my path to spiritual easiness. God showed me what was right and what was wrong during my high school days because I was deviating from my initial spiritual path. Not studying my religion was the most dangerous thing I ever did at the time, had I not I would have ended up like this guy:
[video=youtube;KDY58jYU7BM]http://www.youtube.com/watch?v=KDY58jYU7BM[/video].
Surah 9.123:
http://www.muslimaccess.com/articles/jihad/kill_the_infidels.asp
One verse leads to another, most times verses are used out of context. Each verse has a setting in which it is implied towards, for example: Self defence in Islam and in any sane democracy allows people to fight back when they are being targeted, but suicide is a sin that you will go to hell for, it's said in the Quran.
Surah 5.33, is the death penalty in America any different? I'm a forgiving person, but say the Zionist banking elite are brought to trial in an Islamic country, do you think they deserve a simple prison sentence for the wars they've caused? What about Sergeant Bales, who killed 17 people in Afghanistan for no reason? Do these people really deserve to do what they do and get away from justice?
Again, Quranic verses must not be taken out of context.