Newly purchased Photoshop CS5 - keeps freezing and is unworkable

Question

I just recently ( in the past two weeks) bought the full student edition of Photoshop CS5. Since then it has problems with freezing where the program just stops responding and most of the time when that freezes it force quit wont work so in order to restart it and try to continue my work I have to restart my computer. So far I have only been using it to manipulate photos at a basic level. The size of the images are not that large (13in x 17in at 240 resolution). They dont have that many layers (less than 20 so far). I had tried uninstalling and reinstalling but no change. I changed it from opening in 64 bit to 32 bit and that changed nothing either.
Here is my computer info. Ask if theres anything missing.
Mac OSX 10.5.8
  Model Name:
MacBook Pro
  Model Identifier:
MacBookPro5,1
  Processor Name:
Intel Core 2 Duo
  Processor Speed:
2.4 GHz
  Number Of Processors:
1
  Total Number Of Cores:
2
  L2 Cache:
3 MB
  Memory:
2 GB
  Bus Speed:
1.07 GHz
  Boot ROM Version:
MBP51.007E.B05
  SMC Version (system):
1.33f8
  Hardware UUID:
43BC4078-0CDC-5A87-91F4-07599593F76F
  Sudden Motion Sensor:
  State:
Enabled

Answer 1

Chris Cox wrote:
>> The size of the images are not that large (13in x 17in at 240 resolution). They dont have that many layers (less than 20 so far).
That sounds like you'd be running out of RAM and hitting the scratch disk a lot.
Are you sure that Photoshop isn't just waiting for the scratch disk?
How would I know if it is?