Improve speed : clean or fresh install

[firlrumors]

Applogies for the newbie question.
I notice that my Macbook is getting slow again. The fan starts for nothing even in really cool temperatures and on average it's just much slower than before.

I usually fix this by re-installing everything, but this time I have so many things installed and set-up so I wonder if there's maybe another way to regain the same speed you get after a new fresh install. Like a safe soft that would clean-up your drive and de-fragment it (don't know if you're still supposed to care about this these days).
My internal drive is 700GB.
Macbook is a 2GHz Intel 2 with 4Go RAM - OS 10.6.



Thanks a lot for any help.

 

[firlrumors]

Any advice anyone ?:/

 

[anotherarunan]

If its just the fans - have you considered opening it up and checking if there are any dust blockages?

Although, you could run disk utility's 'repair disk' function - but I dont really think that improves things. Especially if you've recently reinstalled.

 

[firlrumors]

Thank you,
I didn't think about checking about the dust in fact.
I guess the Macbook is not meant to be easily fixed there should be tutorials about how to do it safely out there.
Thanks !!!