windows probably used the space you emptied to get the page file to the size it needed, from the sound of things it may even need more.
The best thing to do is backup all your files in your documents onto disk, or another pc on the network if you have one, and delete.
To find out where all your space is being taken up, open C:\ drive, then right click on each folder to see it's size.
Start from the biggest one, and determine what's inside it, and decide if you need it, if you don't, delete it, or if it's files you can put on CD or another pc or drive, do so then delete it from C:\ to free up space.
Files like Program Files will have more folders in them that have more programs, look at each folder to see the size and determine if the size it is taking up is worth it being there.
I advise you to get a larger hard drive, as it seems like your current hard drive has become too small, it's best to get this C:\ "ghosted" or "mirrored" onto your new one, to save you have to reinstall all your programs, but if you don't mind that, a fresh install of windows is advised.
If you can't afford to do this right now, you have to face facts and start removing stuff you don't need.