Phobia of Islamophobia

I know very well that there are terrorist attacks and violence committed by Buddhist or Christian fanatics but they make up small number of terrorist attack globally. Majority of religious related terrorist attacks committed within last 15 years were related to Islam. I would recommend you familiarizing yourself with statistics like percentage of Islamic terrorism globally (altogether in Western countries and Asian/African countries). Check up article "Islamic Terrorism" in Wiki. You have link and reference to every single terrorist attacks listed there so you can verify facts.

According to a 2007 poll conducted by the PolicyExchange think tank in Britain, 37% of 16- to 24-year-olds said they would prefer sharia law.

2016 survey for Channel 4 documentary finds 23% British Muslims want sharia law.
Half of all British Muslims think homosexuality should be illegal.
21% of British Muslims decline to condemn stoning adulterers (5% openly support them).
Source - Guardian article called "British-Muslims-strong-sense-of-belonging-poll-homosexuality-sharia-law".

22% British Muslims disagreed that religious leaders who supported terrorism should be removed.
29% thought that the holocaust occurred, 2% denied it happened entirely, 17% think it was exaggerated (which is the stance proposed by most of today's holocaust deniers), 24% said they had "no opinion" and 23% didn't know what the holocaust was.
Asked if they would prefer to live under Sharia law or British law, 30% said Sharia while 54% preferred British law
Source: "NOP poll of British Muslims for Dispatches"

Regarding your common Old Testament argument, I read parts of Bible and whole Genesis chapter. I know well how much violence there is and how much genocide and suffering it caused into the past. Bible is violent and genocidal but as violent as many verses of Bible are, they cannot be compared to amount of hate and murder cherished in Koran.
Also, although Christianity used to be much more violent in the past, especially Dark Ages, it has reformed dramatically since then. Islam has not reformed since 6th century and is refusing to reform. Any attempt of criticizing this ideology and suggestion of reform is being aggressively refuted by Islamists and people who question Islam are called Islamophobic (criticizing ideology has nothing to do with being prejudiced against individual people), which persistently and conveniently shuts down attempts of any criticism.
Also, Christianity may perpetuate the value system based on punishments for not following "godly" behavior but it offers little of the reward and praise for being violent towards LGBTQ, women, non Christians etc.
Islamic teachings are designed around complex system of reward for committing violence against "infidels", LGBTQ, apostates (those who leave Islam) etc.
Enough with Islamic apologism. The problem with religious fundamentalism are not religious fundamentalists but FUNDAMENTALS of religion. Not every ideology is equally violent. Some religious or ideologies are more violent than others. Same as some political ideologies are more violent than others. Green Socialism is not as violent as free market Capitalism, just as free market Capitalism is not as violent as National Socialism.
The fundamentals of Islam are built around perpetuation of homophobia, misogyny, genocide, revenge etc. Everyone who claims that Islam is a religion of peace is ultimately either completely morally distorted by their violent delusion or maliciously dishonest. And yes I know that there have been few good things which Islamic world have brought like some poetry or some technological inventions (which is a tiny fraction in comparison to what Western world has invented and discovered, especially after Western scientific revolution. Vast majority of scientific books and literature is not even translated to Arabic. Tiny Greece annually translates five times more books from English than the entire Arab world. I recommend checking up UN's "Arab Human Development Report".) These few positives cannot justify worldwide destruction and violence which this ideology perpetuates, every day.? Like you said, you have to look at value system and behavior developed around certain ideology from historical point of view but also geopolitical and cultural.

" 'Honour crime': 11,000 UK cases recorded in five years"
http://www.bbc.co.uk/news/uk-33424644

Sarah Haider: Ex-Muslim (Thinking Atheist)