On what were the pictures taken - ipad or camera? You said they were all on your computer. Did they start out from a camera with SD cards? If so, then did you keep the pictures on the sd cards, or did you format them and wipe the cards clean? ( I keep them on the cards as an extra external, number them, and list on paper the events on each card.)
The picures from your computer have to be somewhere on your computer. If you have a mac search pictures and even your trash. Do you have iphoto or Adobe Elements or another editing program turned on? Elements tends to take over your pictures when you upload them from your camera. Did you use a program that came with your camera to first get them on your computer? Were they edited?
Do you use Picasa or Snapfish or another program to share them? See what you can find there if you did.
If the ipad/icloud doesn't solve your problem you might have to go the expensive route and take it to someplace like Best Buy. We had to do that in 2010 when a microsoft security update fried our computers and therefore, our hard drives. I had well over 9,000 pictures on mine, and I had scanned, edited and cleaned more than 3,000 by hand that were taken in the days before digital. Best Buy got back all of our data and all of my pictures, even those that were deleted by Adobe Elements edits. (Because of my hopes over four years, I never emptied trash, and those original photos that had disappeared were there in trash!)
The hard drive on your computer is not fried, only full, and it might not be too expensive to do. If you know how, you can take out your hard drive from your computer and try it in another computer and see if you can find the pictures. If you have laptops, it's easier to do that. If that works, you can put all your pictures from the computer on cd's, and then put them on what sounds like a much needed new computer. A Best Buy could even help you with that for les$ than dealing with a fried hard drive.
Another option is to buy and set up an external hard drive to your computer and MOVE (not copy) all of your pictures to it. It will free up space. (Check to make sure they got to the external safely!) Then use another computer by setting the external up on that one, and copy the pictures to cd's that way. And again, your lost pictures might show up.
I know I went on, but I know the feeling of trying to save all of those valuable pictures.
Hope this helps. (Meanwhile, in the time I took to write this, many more might have responded with a simple solution.) If that solves your problem, great!!!