Soruce RPM installed content into /usr/src/redhat/SRPMS directory. I want to change that to /root's home directory, can I do that ? if yes then how can i do that?

One way to do that is to set custom values for %_topdir, %_sourcedir, %_specdir, %_srcrpmdir, %_builddir, and %_rpmdir in your ~/.rpmmacros file. eg., I use the following line: %_topdir /home/rishi/devel/redhat

Ref: http://www.ibm.com/developerworks/library/l-rpm2/

Cheers, Debarshi