My MacBook got a fujitsu hard drive in april 2008.

Not really an a "normal" length of time for a drive to function under ideal operating conditions. Hard drives like any electrical product can fall foul to manufacturing defects, but also knocks and bumps, rapid temparature changes etc...
Have had a mac book since they came out, and my hard drive is still going and it goes everywhere with me , so sometimes I guess its just badluck if your HD goes, luckily they arent too expensive to replace, any 2.5" Sata drive should do. If your mac is less than 2 yrs old, might still be under its applecare warranty, if so they will fit the drive for you free at your local apple service centre