I have a 3year old mac laptop that sometimes seems to take forever to edit images, open large images and in general work with 2400ppi 4x5 scans. I would like to fully optimise this laptop and the operating software for this purpose. Could you please advise me of the necessary steps? below are my hardware details. I am running Lion on it.

Hardware Overview:

Model Name: MacBook Pro
Model Identifier: MacBookPro4,1
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: 4 GB
Bus Speed: 800 MHz


Hitachi HTS542525K9SA00:

Capacity: 250.06 GB (250,059,350,016 bytes)
Model: Hitachi HTS542525K9SA00
Revision: BBFAC3GP
Capacity: 249.2 GB (249,199,591,424 bytes)
Available: 54.55 GB (54,547,599,360 bytes)