Both Python and ASP are well suited for web development. However choosing one language over another truly depends on the type of website you need to create.
Python is a scripting language that can be utilized to accomplish a plethora of things; including website development. In fact Google's App Engine platform has amazing support for creating and hosting web applications written in python.
The only tricky thing with python (assuming you are not using a specialized host) is that it's a bit difficult to get up and running. For example, it is not recommended to run python scripts using simple CGI, for reasons that I recommend you research. Therefor you have the added complication of learning mod-python, FCGI, or some other alternative.
The benefit that ASP offers here is that it is geared toward web development. Therefor you do not have to worry about the best was to serve your applications. Another added benefit that ASP offers to novices is Microsoft's development environments. Because they are geared for web development creating forms and pages as well as utilizing AJAX elements and handling data is very simple, and for the most part can be done using a graphical interface.
The drawback of ASP is that you have to have a windows hosting solution.
Putting my own prejudice aside, why not consider PHP?
Either way, I think you should decided what type of website you want to create.
However, to give you my affirmative answer, if you are just trying to learn something new I would choose Python.