ERP Performance

For Performance Monitoring I am doing following practice

Platform:- R12.0.6 , Database:- 10.0.2


1)top command

confusion:-
User:- oracle , root 
command:- oracle, frmweb, java, httpd, kjournald  (what command means)

C an we kill those process which is taking more CPU???

2)sar 2 20 (from db and apptier)

Confusion:-
how it runs on AppsTier and dbTier

3 )Gather Schema Statistics   

4) AWR Report for database Issue

5) EM Console

Can i use all of these tools for performance monitoring , Kindly share yours experiences. It will be good for me.

Note: - Actually some time not always our user facing problem in slow forms performance, Slow running concurrent request.