Spiders and other bugs dead?

I live in what is called a "garden view" apartment. That means the bottom half of the apartment is underground and the bottom of the windows are level with the parking lot. I enjoy living here and I realize that bugs come with any apartment, especially garden view. I have ran into a few spiders but nothing major. And all of the spiders are different. I have not seen 2 of the same kind of spider. The biggest ones seem to enjoy my bathroom, the small ones that have longer legs (but not daddy long legs) move very fast and they are very hard to see because they are so light, they enjoy hiding under things that are in corners or up against the wall. The past few weeks I have been rearranging my living room and I have noticed A LOT of dead spiders in between the carpet and the wall. I have found about 10. I have never bombed my apartment because I am a single parent and have my 1 year old all the time so I do not know what is killing them. The dead spiders are a nice size, about the size of a nickel some are the size of a dime. My fear, and question is this: are they dying because a bigger spider is killing them and I just haven't seen it yet? Another question, and fear is: Did they lay eggs (i really don't care if it is called "eggs" or not, it all freaks me out) somewhere in my apartment and that is why they are dying? The do not just die anywhere, i always find them where the carpet ends and the wall begins. And I don't see them until I get down there with my vacuum attachments. As far as I can tell me nor my son have been bitten and I have lived here since october. I just want to know why these spiders are dying. Any help would be great! sorry this is so long. Thank you very much. P.s the other dead bugs are just those long things with a lot of legs that run really fast and they almost seem see through and kinda flat. Btw, do they bite?