I guess it rains a lot in the phillipines ?
that is deffinately bad that your brother turms off your note book without doing an orderly shut down. XP has something called a registry that is like a data base, that when you do an orderly shut down xp takes apart and puts it into a file. Then when you start again xp takes that file and builds the registry. If you just turn off the pc, some data may not be saved , fortunately xp has a back up, though problems can still occur.
try going to spywareguide.com on the right side of their web page is a free spyware scan / remover
also try this
unfortunately your pc maybe in a state that only doing a WAR ( wipe and reload) will cure.