unable to use I photo or Aperture since upgrade from mountain lion to mavericks

I have a macbook pro 2.8 GHz intel Core i7 memory 8GB. As soon as I purchased the upgrade my laptop froze, I took it to an Apple store where they replaced the hard drive but where unable to fix the IPhoto. They advised me to buy Aperture to store my photos. Since then my computer keeps shutting off as soon as I try to work on a photo. brought it back for repair and was tad they could not find the problem. I was thinking that I should downgrade back to Mountain lion as my laptop was working perfectly then.
I am very discourage and I don't want to buy a new computer and waste this one. I am very dissapointed by the service of the Apple store at the chinook branch in Calgary Alberta,Canada,