Ralph,
FrontPage (which is no longer supported by Mirosoft whatsoever) and Blue Voda are incompatible utilities, and will not function via importing elements back and forth.
To answer your questions by the number...
1. Blue Voda uses the universal WWW standard of PIXELs thoughout the program with regard to size for all shapes, objects, images, and "page" dimensions. Inches are not translateable, but may be approximated when converting older formats if you have a conversion formula to use as a guide (find one by Google).
2. Because FP and BV are incompatible, you will need to focus on using Blue Voda for the construct of your pages. And, yes, your pages are entirely customizable easily in the drag-and-drop environment Blue Voda was created in, making even the largest update jobs simple and quick. Pages are automatically Saved and your folders updated each time you Publish.
3. You cannot import aspects of FP into Blue Voda, and vice versa: they are incompatible. IF, however, you are tryhing to preserve the total build of your previously FP-created and elsewhere published pages, you can use an inline frame (iFrame) to "present" your earlier pages 'on top' of a BV created page (where you can construct the borders, navigation, etc.), and it will appear that the BV page with iFramed other page are simply one page.
This is something you will need to research here in the forums: using iFrames, and the different techniques possible within Blue Voda. It is too long of a topic to brief down for you here.
4. There are multiple means to automatically update a "templated" page design automatically using Blue Voda, and even manual page-to-page updates are not too much of a challenge due to the simplistic nature Blue Voda allows Users to manipulate items with superb results in the friendly manner it was built on (depending on the number of your pages, of course, it can take minutes or as much time as required accordingly).
My suggestion is that you
download Blue Voda for Free and start using it to create a page or two until you become familiar enough with it to see for yourself how to resolve your issues you are predicting you will face.
You can download Blue Voda, use it to create web pages, and Preview them prior to ordering a hosting account at VodaHost. The Tutorials will clearly outline every aspect of technique you will use to build an awesome website. Be sure to review them in order, as they are progressive and that in itself is an important aspect in web building. You can also pause them to practice the topical instruction right then and there in Blue Voda if you have it open when reviewing them --- a great way to "validate" your learning experience!
Keep in mind you can only Publish a BV-created web page to a VodaHost server, meaning you will need a VodaHost account established to actually publish to the web. The Preview function in BV allows you to create away to your heart's content and see 'live' in an IE browser how the page looks fully functional, but again, that is only on your local system and not on the web proper.
Good to see you thinking, but still no need to put the cart before the horse!