Hey Denise,
don't decide too quickly I would say. If your pc worked fine up till two days ago there must be something wrong.
I don't know exactly what's wrong with it, but since it did work two days ago it's hard to believe you completely broke it.
I don't know your set-up, but it sounds like the RAM could be broke.
If you have multiple slots filled with RAM, try to remove all but one and check how it works. Do this with all the RAM-thingies you have.
It would be even better to check all individual RAM-thingies using Memtest86+. You will have to boot with this program and then it checks all the area's on your memory-thingies(no idea how you'd call them in English
)
If it isn't the RAM, it could be numerous things. You could also take a screen-shot of the Task-manager while you're in Windows . See if certain things eat up all your RAM. Sometimes Anti-Virus or Malware can really slow down your pc.
This is just a start, but it might save you selling your camera-gear...
I'm pretty sure your daughter could do all this with her hands behind her back. Better yet, you could do it yourself
Let me(us) know how it goes.
Edit: You could also start by trying Memtest86+. If there's something wrong with your RAM it will quickly show. After that you could do the testing on the separate RAM-thingies if you have more than one.