Ok. so you:<quoted text>
Judaism is a communal religion - therefore there are organized movements. Most localities in the US have their own Board of Rabbis which more or less define the acceptable standards by default. They dont have to accept each other - but they get along enough to function together to set communal standards for things such as Kosher certification, social work, educational opportunities, and burial. Usually the movements represented include the Orthodox, Conservative, Reform, and Reconstructionist.
Obviously there are gazillians of unaffiliated Jews as well - but at the end, it is a tribal religion therefore participation in a synagogues from one of those movements is really necessary to practice of the religion.
Within and between those movements there is a great diversity of "belief" regarding the status and authenticity of scripture. Basically as long as you dont follow Jesus, and as long as you are not a practicing polytheist, you can probably find a niche somewhere.
1. Don't have to believe in god.
2. Don't have to believe any of the books.
All you have to do is:
1. Not believe in JC.
2. Not be a polytheist.
And you can show up Saturdays and call yourself a Jew?