Very few spiders can kill you.
Black widows for example, generally only cause death in infants and very young children. Some adults can be allergic to them and risk death...but for the most part, they just hurt like hell (their venom causes random muscle contractions...think of the worst cramp you've even had and multiply it by 20)
Most house spiders are harmless.
The myth about eating them, or having crawl in your nose/mouth, totally false. Like most insects, they are great at detecting carbon dioxide. Its a defense mechanism, anything that gives off carbon dioxide has lungs, anything with lungs is likely a predator, if not just much larger and dangerous to them... Aside from bigger tarantulas, simple blowing softly on a spider will make them run away, or ball up in defense.
People do -eat- spiders, they are quite tasty (i've eaten alot of bugs...after the first couple bugs you try on a dare, you actually kinda like them, and its good for grossing out people...keep in mind lobster/crab/shrimp are really just insects, their muscle structure is the same as land insects...the only ones you dont eat are colorful ones and ones that stink...those are poison giveaways)
I used to have a serious fear of insects. I dont like being afraid of things, so I studied them. I bought books on them, their biology, effect on the environment...etc. They are quite interesting little creatures. Spiders are high up on teh cool factor...
Anyways...to the point. House spiders dont generally have any poison at all, and very few spiders can be leathal...Black Widows just hurt like hell (bit 3 times, personally...used to be a cable buy...they like peds...those little tube shaped things in yards with the cables in them).
But, and I say this in all seriousness. If you live in the mid-range (north/south) to south sections of america, learn what Brown Recluses (FiddleBacks) look like.
Heres a pic
Their bite is terrible. Painfull, but the pain isnt the problem. They literally cause your tissue to rot off of you. And the process can last for years after the bite...and eventually spread to the heart, and cause death.
The picture in the link below is of a bite to the hand after only 10 days.
IF YOU HAVE A WEAK STOMACH, DO NOT OPEN THE LINK BELOW ... im not even going to hyperlink it, copy and paste if you want to see it, dont want to suprise anyone...
http://z.about.com/d/urbanlegends/1/0/4/B/day_10_sm.jpg