any recommendations on windows-based ISO extractor?

I need to back up a couple of CD’s (not copy, just create ISO files).  Any recommendations?  Something free – there’s lots of commercial ones out there, but I’m not going to pay for something when I could, worst-case, pop it in my linux box and use dd bs=2k 🙂

I tried ones like ISO Recorder, ISO Buster, MagicISO, etc – the ones I’ve run across either have size limitations or are commercial or didn’t work (DVD Decrypter, for instance, only works for DVD’s – I’m surprised it wouldn’t create the same ISO-9660 image from a CD when it had less work to do since there’s no CSS involved).