The program Subdownloader allows you to easily find subtitles from any video file or DVD, i.e., first you download a video/DVD, then you use this program to download Brazilian subtitles.  The link provided has some video tutorials on YouTube, or the figure below may suffice…

I configured the program to only search for Brazilian and English subtitles.  I also configured it to work with mplayer, which allows me to launch the movie in MPlayer by right-clicking on the subtitle. 

If you’re just starting out, this might not be so useful.  I would suggest you work at a slower pace and look at my Movie Subs page or look at the Grammar links on my blogroll.  However, if you understand about 80% of the subs, then it could be useful to read along with the sub while hearing the English audio.