PHP page with dynamic graphic generator

We have an existing website that provides free personality reports to users after they fill out a short online questionnaire. Currently the free report we give to users just contains some text in paragraphs plus some images suitable to their personality type. The images we provide at the moment are simply static GIFs. We want to completely change how the free report page we give away looks. In future, we will give very little text and there will be 3 or 4 images on the page about the users personality. Each image will be customisable by the user so we need some kind of editor on the page to allow the user to select sizes, colours etc for each graphic. The graphics should automatically update on the page when a user makes a change. Once the user is happy they will save the image and at this point the system should actually generate the GIF image and store it on our server. One of the graphics will have to be generated with with user's firstname and lastname on it too. To be clear, we need these images to be dynamically generated at runtime. Below each image will be linking code to allow the user to put a link on their blog/myspace/bebo/website page to access their pic from our server. Users can log back in to our website any time later and edit the settings for their graphics and re-save them. The page you create will be part of our existing website but I envisage it being pretty self-contained so you will not have to do much integration work with our existing system. The image editing facility on our page must look great and be really easy and intuative for people to use. We are open to suggestions about what to use e.g. javascript, ajax, flash etc. Please include your proposed solution with your quote. One of the graphics that will be on the page will be a "postcard". Users will be able to click a button to email this to their friends. It will actually send their friends a link to a new page on our server where their friends can see the postcard. This is similar to an eCard. You will have to build this page too.