Convert iTunes to MP3

Dear friends! Is it a deal to change iTunes to mp3? I say NO :) Its really annoying not being able to play iTunes tracks with my $300 iriver! Digging for a solution brings certain results. To convert iTunes to MP3 I used this tool drm removal (drm-removal.com or something like this, please ask me - will find that web again). I don't care what is drm - what I read, its something dealing with protection and nothing about iTunes. But this tool really works for me and it converted quickly my iTuines entire library, including video files!. How do you convert it? Why iTunes brings this inconvinience? I didn't like ipods at all! They simple stuck and suck! What is that drm that I loose converting my itunes to mp3? thanks in advance!