I'm trying to write a search enigne. Nothing fancy like google or so, just a simple one for educational purposes. I have done a little research and I know that Google uses Python, Java and C++. I on the other hand know C++, PHP, some Java and C# and even less Python. I see that Ruby on Rails have a lot of heat for some reason.

I am willing to know a new language and framework as long as it isn't to difficult. I want something fast, rather portable, easy to maintain and update.

I have made a few web pages with PHP and ASP.NET C# but really simple things.

So which of these languages will meet most of my requirements.

A search engine means alot, from small-scale (like daniweb's search box) to large-scale(like google search engine)...
The kind of language you need depends on the kind of search engine you want to design and its flexibility and usage.