I have about 1 year professional experience with C# and ASP.NET and now I have a small web application idea I want to implement but I don't want to use ASP.NET to implement it due to hosting fees and other Microsoft corporate yada yada.
I want to use python/django to implement this as it is cheaper to host and a good stack to develop on but here is my problem.
I haven't really dived deep into C# and ASP.NET and I want to. I also want to develop this web app as well. All the great advice on Stack Overflow for junior developers have mostly pointed to learning one language very well before learning another.
What advice would you give? Should I leave this idea on the back burner and really improve my understanding of C# and ASP.NET or should I dive into python/django and develop this app?
Edit
Thanks guys for all the answers, all very insightful. Just to add, I really want to go deep in c# and I really want to build this site too and as we all know, the power of focus creates massive impact. I am equally passionate about both.
Update
Thanks everyone for excellent answers I have made up my mind and I will stick with going in depth. I will be using mono on ubuntu. So that is c# .net and associated technologies on the linux platform. Then after 2 years look at the hottest thing(s) and learn em.
Thanks guys.