How do you make computer games less laggy?

I have the old macbook that has a 2.1 GHz Intel Core 2 Duo Processor

and the memory is: 1 GB 667 MHz DDR2 SDRAM

I do not know to much about computers, but how would I make my computer games run less laggy? More memory GB's?How do you make computer games less laggy?
Turn down the graphics and sounds and effects. To make them less laggy it's is the ram and the processor speedHow do you make computer games less laggy?
You probably need a better graphics card. Or a different computer because macs are not meant for games. But it does depend on the game to.How do you make computer games less laggy?
turn down the settings. get a multi core cpu. more ram. and most important a better video card.
If you want I can send you detail guide for this. my email address is mak@codsville.co.uk