Macbook Pro getting sluggish and having trouble figuring out why

My Macbook Pro is only about six months old and it's starting to get sluggish. Not slow per-se, just kind of rough some times. For example, videos on youtube will jump every several seconds or so. Or, even now, as I'm typing, occasionally my typing will get several letters ahead of the computer. Then when I stop, it catches up. Or Firefox will take a lot longer to launch than it originally did. Almost all applications are taking longer to quit than they did. And, I'm getting the pin wheel more often than I used to also.

A friend just bought a new Macbook and we got it all set up with roughly the same basic software I'm using and it's clearly running much smoother.

I've done some searches and done most of the basic stuff that people have suggested I do to help with these kinds of problems but I'm not seeing much of a difference. I'm wondering if I've allowed some stuff to run in the background that I don't know how to stop. I've looked at the Activity Monitor, but I can't tell what was there when I first bought the machine and what's new.

Any suggestions would really be appreciated. Or links to articles talking about this kind of thing would be awesome.

Thanks!

Try running Onyx. It will do a great deal of maintance and clean up of your system. You can find it here
Download OnyX for Mac - OS X maintenance & optimization tool. MacUpdate Mac Optimizers Software Downloads

hope it helps
Clay

I had used Onyx once before. I just today used it again per your suggestion. Other than feeling good about knowing the system is clean, I'm not sure it's made much difference in the performance. Are there any other suggestions?

Run activity Monitor - in Apps/Utilities - see which process is hogging the scene and sort that one.

How full is your hard drive ?
if its almost full then its normal your mac is going to act a little slow off the mark. As for firefox, it has its day when it wants to work. i dont think that has anything to do with ur mac.