Still not that much space

I've been having issues with my computer lately. Storage issues, to be more specific. I've been getting all these nifty alert windows that tell me that I'm running out of space. In fact, I couldn't even download the new Taylor Swift CD onto the computer because there wasn't enough room for it. In checking the computer information, I've discovered that it's barely clinging to life. My 120 GB drive is struggling. I need more space.
Brian and I did some research and discovered that I can replace my drive with a solid-state drive, wherein there will be plenty of space, and no chance of a crash. This is the best and only upgrade I can do to my computer at this point, since I'm not interested in a new machine just yet. I stopped at an Apple shop today to pick the guy's brain, and was assured that what we had seen was possible, and that it's certainly financially feasible.
But as I thought about my storage information, I started considering ... again ... what was taking up all the "other" space on my computer. The only really huge amount of space I could figure would belong to the pictures. My iPhoto file, probably, is huge. I don't know how to check it individually, so I thought to conduct an experiment.
I take a whole lot of pictures. Like, a whole, whole lot. So to go through the images I have on my computer and clean out the blurries, duplicates, uglies, and unknowns would be a huge task. I've never filtered through them, ever. But I spent a couple hours doing just that today, and from the pictures taken between May 2006 through September 2010, I deleted about 1,000 images, probably more. At that point, I checked my storage, and lo and behold, I had 5.85 GB of empty space on my computer. I figure, by the time I catch up to the present, I'll have 10 GBs at the minimum, available on the computer. This is amazing, obviously, but I think I still may go ahead with the solid-state upgrade.