Muslims claim jesus never died. they also claim he was a (true) prophet. however, jesus prophesied his death many times. therefore, either jesus did die, since he was a true prophet, proving islam false directly, or he didn't die, making jesus a false prophet and islam false indirectly. either way, muhammad was a false prophet.

www.apostatesofislam.com
www.faithfreedom.org
www.jihadwatch.org
www.prophetofdoom.net
www.exmuslim.com
www.formermuslims.com

and just as an aside, the birth and death of jesus of nazareth are historical facts not debated by any educated people, whereas his resurrection is a matter of faith.