Well of course I'd recommend what I use, which is
Railo CFML - has a nice easy learning curve and is brilliant in lots of ways.
:)
Rendle would probably recommend
Ruby, because he uses/likes that.
Python is also popular for web stuff these days.
All these options are modern/active/etc and have plenty of tutorials and help available online, all have good web frameworks available, and are capable of easily creating a blog application, or whatever else you might want to do.
There are other choices too, but I'd suggest picking one of the above (or maybe even check out all three) and see if you like it/them.