24 is not even half of Lost (is a suspensful thrill series, but really has only Jack bauer going for it, its story is in a loop, high production quality, but so so writing), and I said that as someone who watched 24 for 7 seasons now. 24 is decent, except few seasons like last one that was crap.
But Lost, despite its confusing filler moments in season 2 (dragged it a bit), is an epic series, like non other on air (only one that gets close is Battlestar Galactica). Its writing and acting is as good as it gets on tv series.
I understand why someone who dont watch it would be put off, because when the see it, its in the middle of story, its the worst kind of series you can just hop on and try it in the middle of it all, you will just get confused and wont know what to think, its just too complex, beyond belief (even for regular viewers, you wont get anything of seeing a random moment as a non viewer). Its a must to see it chronologically to appriciate it. Aslong as one gives its a shot from the get go, it will be easy to sense why its the most popular tv series by far.