Adobe has a whole bunch of collections - the trick is to find the bundle of applications that apply to you. You should look at
http://www.adobe.com/products/creati...ing-guide.html
You have said you want to scan in blueprints and want to develop a website.
For developing a website, the Adobe product that applies is Dreamweaver, and maybe Flash Professional (depending upon what sort of site you want to do).
For scanning in blueprints, the closest match is Acrobat (to make PDF out of them).
However for both of these there are less expensive alternatives
For generating HTML based websites the alternatives are legion and will depend primarily upon the platform you are on - on the mac SandVox and RapidWeaver are popular alternatives.
For just scanning in blueprints any scanner should come with basic software that will let you save your scans as any of the popular image formats - so you should not need any additional software to just do the scanning - the question is what do you want to do with it afterwards.