As per your question regarding the BizTalk server, it good for you as you already have the experience in .Net because it's good if you have the knowledge of .net with BizTalk server.
As you know that BizTalk server is one of the integration tools from Microsoft which is used to integrate various applications across the organization.
So its future is always good because if any organization is running with some applications and tomorrow they want to create a new application may be in some other technologies then they need to integrate the new application with their legacy applications so that time the BizTalk server will be in use.
Also lot of companies is looking out the BizTalk server professional now days.
There is no need to learn any new programming language as it runs only on Visual Studio IDE so for you there is nothing new..also the whole BizTalk server work based on the properties and configuration..very little time you will get to do the code when some custom kinds of things are needs to be implemented..
So it's quite easy to leans and then work on it. The next and good thing is that if you have experience on .Net and BizTalk server then salary package will be more and you will be entitled for permanent job position becoz most of the people think that BizTalk server means temporary job and its true becoz they don't have knowledge about the .net ..
so as the projects will be less compare to .net projects..but if you have the knowledge of both .net and BizTalk server, the companies will prefer to you more compare to only .net guys as they can shift you in both as per the requirements..
As I m not in Bangalore so I can't tell about the institutes there...you can search through your friends..websites or any other medium..
Pawan Awasthi(DNS MVM)
+91 8123489140 (whatsApp), +60 14365 1476(Malaysia)