I guess the best advice is to download a known working rom, as an example OGOs gingerbread which works pretty good, or blayos froyo, both are htc sense based, or you can go for cyanogen 7.10 (Latest stable) these all are working roms for the legend.
best advice is to always keep copies of the clockworkmod (fakeflash) recoveries in the root of your SDcard and backed up on your PC this way you should never have the issue of not being able to boot, the booting clockwork mod (Fakeflash) is always named update.zip.