FREE sofwares needed which are good and virus free!

I am new to the forum and i hope this is the right place to post!

Guys i play games online,like DOTA and CS in the platform GARENA.

I would like to record my games to make movies and sorts like that.
So please tell me good free softwares and links to it.

and i face online threats much

So please also tell free softwares which are good to eliminate virus,spyware,adware etc etc...

Also i would like to get video convertors,which supports most formats and that to free

Thanks for the help.

(I aint a geek,so reading this post may seem funny to you!)