Improving speed on iMac mid 2007 w/Lion

[zarmati]

So i've noticed that my iMac mid-2007 model
(Processor 2.4 GHz Intel Core 2 Duo , Memory 2 GB 667 MHz DDR2 SDRAM and Graphics ATI Radeon HD 2600 Pro 256 MB)
has relatively slowed down since i've updated to lion. When I was running leopard it ran much smoother. Simply task like opening iTunes and Safari take time and sometimes don't even open. I have 4 accounts ( don't know if that affects anything) and 149gb of space left .
Is there anything I can do other than re-installing leopard to maybe "boost" my computers performance/speed? (Deleting apps doesn't seem to help)

Thanks!

 

[Intell]

Upgrade its ram from 2Gb to 4Gb or 6Gb. That'll make it much faster.

 

[GGJstudios]

Performance tips for Mac OS X

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