Magento

first thing i would like to applaude the team incharge of bringging magento to life, wonderful job guys, really.
i am an old MS veteran but quite new to php and mySql, so naturally i would look for MS technologies when starting my new e-business but i came across magento and thought why da heck not so here i am waititng for the final version to come out.
now before i start is there a package that contains the needed extensions, the list totaly bafled me
what are PDO/MySQL,MySQLi, mcrypt, mhash and simplexml anyway?

Try this guide: Magento Installation.