I have a Macbook I bought almost 2 years ago…
It’s been a blessing but lately acting a bit weird 
It jams quite often even when I’ve hardly opened two programmes …requires me to force shut down quite often and for past week or so gives somewhat light vibrating sound …Don’t know what’s wrong with it…
It is Mac OS X version 10.5.8
any idea???
Re: help please!
Macbooks (like all laptops) are not designed forever. Especially after you have droped them or spilled stuff on them, 2 years is a pretty long time for a Macbook. Its probably overheating with a fan problem. It can be repaired, if you want to do it yourself or know anyone it would be the cheaper option. Otherwise some monkey will charge alot just to look at it.
Contrary to popular belief Mac viruses and adware do exist and their numbers are increasing and other threats affecting Mac OS. You could try some checking out your OS with Kaspersky Anti-Virus for Mac or other anti-virus.