If you don't have extensive knowledge of OO programming in PHP and Zend Framework I don't recommend you to install Magento.
I don't agree with this at all. I'm developing my 1st Magento project for a client of mine and I'm no PHP or Zend wiz...in fact, I'm on the boards right now looking for info about Zend Optimizer.
Bottom line is that it's a lot of work and lot of research but the web is full of excellent reference material and I've found people to be very helpful on Magento's boards and on StackOverflow.
If any one has any questions they can PM me.