Yes
Yes, it does include an audio jack in the front console. I'm not sure about MP3 discs though. There is only a mention of that in the option for the Audiophile system which seems to be an option only on the XLT and Limited (Gas). There is already debate over whether or not that system is part of the Nav package.
With or without the Navigation system the (Gas)Limited, Hybrid and Hybrid Limited come with SYNC which will work with an iPod or other MP3 player. However, I have heard that the SYNC system is even better and easier to use if you get the Navigation system. I ordered mine with the Nav but I'm a sucker for fancy technology and things with buttons :D
That is true, but it is the base price for the FWD model not including tax, destination fee, etc.
Hope this answers your questions.