Hi.
I'm not sure about a laptop with Vista (I'm not a fan of it, to be honest), but I had speed issues with my old IBM laptop with XP.
It's a good idea to check all the software you've ever installed - maybe something you didn't want to install got installed and is causing problems.

Also I got Auslogics BoostSpeed made my laptop a lot faster. You can download a free trial version.
Hope this helps.