first, Spectrum Games are not ROMS.
Because there are not much cartridge based game exits in spectrum scene. They are tape image files or memory snapshots (maybe second one could be called RAMS but still not ROMS)
Second, many of the spectrum games and utilities at www.worldofspectrum.org (largest zx spectrum archive) are free to distribute and 100% legal.
And third, I'm writing this because I'm so bored today.
Edit: on second thought, maybe spectrum games and utilities at www.worldofspectrum.org aren't free to distrubute,but you can download and use/play them.