>Is learning VB.NET going to be much easier than for example Delphi?
If it's from ground zero, I don't think so. Delphi is so much user friendly. To me, I would rather invest my time learning Java rather than VB.Net or Delphi. By doing so, I have the leverage of going into C#.Net if necessary with the assumption that .Net is a success which I think it is.

>One thing is certain, you skills are portable, your existing projects (and investments in code) are not.
Portability to where? Different platform? Staying into VFP will make you insecure as far as portability issue is concerned. With Java, you have the confidence that your investment will give you returns long term.