Microsoft blows big cow balls. PHP is far superior. If a company is using .NET, they are totally wasting their money. You can find jobs with PHP left and right. Don't listen to these .NET mindless zombies.
For corporate websites and intranets, .NET. PHP is more popular for small business and personal websites because it is simple, free, open, and portable. There's probably more money in .NET.
I am doing Engg. in Electronics and telecommunication. HAve sound knowledge of C and C++. I wanna study either PHP or .NET ... Can you tell me wat should i do with respect to the current demands and how long will it take to study them.
PHP is easier to learn and .NET is good too, but I would recommend you try some ERP or Business based software as that sure will help you last longer and enhance your career faster. Another good area would be Security & Audit especially in SOA (Service Oriented Architecture).
PHP today is a trend and many corporations are using it because it is less expensive to maintain, therefore .NET is a strong language and largely used worldwide. Based on your knowledge of languages you might be better with PHP since is a variation of the C++, but C# is very similar as well.
Give a test run on both and see which one you are more comfortable with.