I don't mean for this to be a rhetorical question, but why is it that you go to your local computer store, excitedly purchase the latest and greatest laptop, only to have it slow to a crawl a few years later? I have found this true of all windows operating systems. I don't know if it is like that on the MAC. It just seems to me like someone (Like Microsoft) could build caching or application management into their OS so that peoples machines are not so slow. I sped mine up a little bit by choosing the simplest screen saver. I also undid some terminate and stay resident applications like Skype. However still my laptop is only 4 years old with 4 gig and it is pure torture to actually try and write an application in my compiler and not have my PC take an excessive amount of time. I really just think Microsoft could raise the bar on making a more proactive OS.
I now have a I-5 Machine at work with 8gig of ram and 500 gig of hard drive space. It also can be slow at times. I now, no longer look forward to buying the latest and fastest processor based machine, because in the end everything just ends up running slow in MS Windows. I can just imagine how many man years are wasted each year because of slow computers. Sad, but true.