huzzah for composing! If all goes well I want to become a Film and Video Game composer, along with performance as well. I'm in college for music composition right now (freshman)
Nothing wrong with midi, but whenever you have the means, get better stuff.
Software I use: Noteworty Composer (good for exploring midi effects and balance), Finale (for proper sheet music purposes), Logic (Electronics, effects, you name it, does a lot), Acid Pro (good for more electronics, effects, but less than Logic), Nero (more stuff for effects), Garritan Personal Orchestra (AWSOME sampler program for real instrument sounds instead of midi)
I'm trying to set up a website. I've got a few performances recorded that I'm gonna put up online soon. I posted my list of compositions in my gaia journal:
http://www.gaiaonline.com/journal/index.php?mode=view&p=3222135