Hi, I'm just about to start designing a mobile version of a site, and i was hoping that maybe someone could help me with the following few questions please:

01 - is a mobile site essentially just a normal website that is designed and coded to work well on mobile browsers, as in can you just design and code a normal HTML / CSS website that has a single column layout with big buttons
02 - is there a mobile web framework out there that a lot of leading mobile sites utilise
03 - is there a generic web standard default width size that the canvas (width of the site) should be... what width should we all design our <body> to be so that it fits all current mobile devices (iPhone and android) or should we just code everything to 100% width in a single column layout

Thanks in advance to anyone who can help with the above questions...