¿Mande? is NOT pronounced like Monday. Most English speakers pronounce "monday" like "munday" and that is definitely not the "a" sound in Spanish.
Ice is "hielo" and if you pronounce it like "yellow" (with the exaggerated "w" at the end) you probably will be understood but I think it's better to learn the correct pronunciation - it will make learning and comprehending Spanish a lot easier later on in your studies.