Yes, a Frontpage site (any version) is easily transferrable between
Frontpage versions. The latest FP version is Frontpage 2003. However, this
has now been replaced by Expression Web Designer.
Expression Web Designer, the new product on the market aimed at
professional developers as well as hobbyists. You can easily open a
Frontpage site in Expression. It may take a while to get used to
Expression as it is very different in some respects, but definitely better
in the long run.
It produces standards compliant, and cleaner code than FP did (in that it
doesn't use the 'webbot' type features that Frontpage did). It leaves it up
to the user as to what scripts they want to use to create the same functions
FP had built in such as discussion forums or guestbooks etc. That said,
Expression doesn't touch existing webbot functions, but also doesn't allow
you to add any. If you do need the specific FP functions, you can open the
site in FP and add the webbots there.
It will be worth doing a "clean-up" of your code, and some converting of the
mark-up formatting to CSS. This may involve getting to know how to
hand-code the HTML, because knowing HTML and CSS coding will be a definite
advantage in using this tool. Replying totally on the GUI will only allow
you to probably make 50% use of this product effectively.
Note, this in itself involves a slight learning curve if you're not already
familiar with CSS. The clean up of your code and using CSS will allow your
sites to (more likely) show as intended across a wider range of browsers.
For tutorials, Google "Expression Web tutorials" and/or "CSS tutorials".