I need advice on installing OSX on my Dell 1525

I've done lots of reading on the subject

What I'd like to know is: what will I be missing if I install?

What I've read: you can't really get a perfect install - 'something' is missing normally

So... before I installed... I just wanted to know what I might be missing?
(I have read this up - but am confused - different list state that different thing will be missing)