I bought a Raspberry Pi Starter kit online (and it came with a sd card), and had it running Raspbian. I then went and installed Rasbmc on it and I corrupted my SD Card. I wiped it clear and then installed Noobs on it and ran Rasbmc. I wanted to go back and install Raspbian on it again but it said I did not have enough memory. I wiped it AGAIN and installed noobs, plugged it into my raspberry pi and it said I did not have enough memory still. Since then, I have tried formatting it several times but I cannot get it to clear. I am trying to do this from a Mac.
I cannot comment so I'll have to post this as an answer. What size is your SD card? Somewhere I read that the latest versions of Raspbian require 4GB+. I have found that NOOBS often requires a bigger size because it has an installer and then also has the operating system you want to use (Raspbian, OpenELEC, RaspBMC etc etc).