Adobe Photoshop CS5 installing difficulty

Hi.
I am having difficulty in installing the Adobe Photoshop CS5 on my mac. My configuration is

Model Name: MacBook Pro
Model Identifier: MacBookPro3,1
Processor Name: Intel Core 2 Duo
Processor Speed: 2.4 GHz
Number Of Processors: 1
Total Number Of Cores: 2
L2 Cache: 4 MB
Memory: 2 GB
Bus Speed: 800 MHz
Boot ROM Version: MBP31.0070.B07
SMC Version (system): 1.18f5
Serial Number (system): W8723CVQX94
Hardware UUID: 00000000-0000-1000-8000-002332A09AC6
Sudden Motion Sensor:
State: Enabled
can you please help me with this.

— Pranjal Mehta