Which is the most difficult career path in I.T to learn.?

Well personally it all depends on what level you learn them to. For example networking can be quite easy, unless you start to really get into the details of it and learn about modulations and transmition methods like FDMA, CDMA, TDMA etc. A CCNA is quite easy, a CCIE isnt... get the idea? Same deal with databases, learning the basics of MySQL and PostgreSQL are quite simple. However there is a reason that Oracle DBA's get paid a shed load of money...because its a damn hard job. Web Design has to be the easiest out of the lot, but it often takes tallent to create a good looking and functional web site, not everybody is born to be a designer! If you are just starting out id say why not look into all of them and find out what you enjoy and what you are best at.

If you put your mind onto one of the fields that is of your interest.... and give it your best short.. all the fields would be come easy!!

Networking and programming would be very fulfilling provided you can grasp the fundamentals of it quickly. Otherwise it will turn out to be a disaster if you are stuck in it for a long time without any progress, so better be a better judge yourself. Network and System administrator, I assume would be easy to pick, I myself considering it for the very reason, to shift my track to these specialization.

you better think in many way