In other words, yes, you do have a disk space issue.
First off, seriously consider upgrading your hard drive. A 500 gig hard drive is probably under $100 (Haven't looked in a while, but check newegg.com and macsales.com)
Second, your problem is most likely related to your lack of hard drive space. As a previous poster mentioned, your MacBook Pro is designed to write a sleep image to the hard drive (in addition to memory) before turning on the blinking light. This is so if the power source (battery or adapter) is removed, the computer can still recover using the non-volatile image written to the HDD.
If you want to disable this and speed up your time to get to the blinking light, you can enter this command in Terminal:
Code:
sudo pmset -a hibernatemode 0
For a little more info about safe sleep, and how to switch between the modes, read here:
Safe Sleep Information