I want to know what are the options to do some scripting jobs in windows platform. I need functionality like file manipulations, registry editing etc. Can files be edited using
Batch files are the most portable, but doing complicated things can get hard (very hard).
Powershell is incredibly - um - powerful, but the installed domain at the moment is only slightly more than those people who like using powershell and servers they administer. If you control the machines you're scripting on and can mandate that powershell is installed, powershell is the way to go. Otherwise, batch files are the best way.
Powershell lets you do anything which can be done, but some things will be harder than others :)
(Seriously, if you want to control a windows GUI app from a script, you're going to have a lot of pain unless the app supports scripting itself, or you want to start posting messages to dialog controls and screen scraping the dialog to check for success.)