You're probably getting a cropped sensor camera like the 450D or 40/50D, so the 50 mm is 80 mm field of view. I personally find it not as pleasing to use as my 100 mm (160mm), though the f1.4 is great for low light.
Generally, when I do casual snapshots, I use the kit lens since it's light, versatile and can focus close distances. For serious shoots, it's either 50, 100 or the 200-500 depending on subject. People always recommend the 50 mm so it's alright to just get it even if you don't know what the hell it is, because you will only truly start to appreciate the power of an SLR with multiple lenses.