Regardless of semantics, the Allah of Islam is not the God of the Bible. The only sure way to heaven for a Muslim is to die a martyr, while slaughtering "infidels". Blowing up innocent Muslims as a "suicide bomber" would be a one way ticket to hell for a Christian, whose only hope for salvation is a repentant heart and faith in the finished work of Jesus Christ. These are obviously two completely different concepts of God. There can be no arguing that.
Find a New Testament in Arabic to see where Allah is found in "The Bible". You might trouble yourself to find a Latin Bible where you can discover "God" is nowhere to be found. Your local Catholic church can probably provide you the opportunity.
"Lah" is a word that can be associated with "Moon". "Deus", a Latin word for "God" is clearly a cognate of "Zeus". We can play wordgames all day long, but you are correct that we have to look at the nature of the deity invoked to see if we mean the same thing.
It's quite possible that there are individuals out there whose view of God is erroneous, irrespective of the name used.