Okay, I know there have been numerous other posts about this problem, but I've looked at a lot of them, but none of them seem to help me.
okay, here are the details...
I bought an MPB 17-Inch, late 2011 model with OS X lion installed, It has a 2.4ghz processor (i7), 8GB of RAM, and a 750GB Hard-Drive @ 5400 RPM. I was eager to purchase it, because I had heard some rumours (at the time, which they turned out to be right) that they were going to phase out the CD drive in the 2012 model (my face felt like sucking itself into my skull when I saw that particular rumour).
when mountain lion was announced, I was eager to get that too. I got it and it performed pretty much the same as Lion (with many enhancements to boot). but then I started reading articles on how macs are slowly getting more vulnerable to viruses, so I installed MacKeeper to aid with that (then as time progressed, more software came, figures...)
slowly my external hard-drive rmaintaining my backups started to fail me, and I could no longer store backups from Time-Machine in it because the volume of the backups were larger than the hard-drive itself. I panicked because I hated the idea that my macBook was now vulnerable to be permanently screwed up if it did.
so with backups being stored on my Main hard-drive (until I find a good external one that is bigger than my internal one), it's taking up some space, maybe 54 GB.
my problem is that every app seems to stop responding, or go INCREDIBLY sluggish (even the finder), at random, for no apparent reason. I've also noticed there's also no animation on the grey apple going to the top of the screen on startup, and there's choppiness in the full screen and calendar month-view "page flips", and there's sometimes a lag when trying to get into the menus in general.
I've gone through everything I can think of, MacKeeper clean-up, Disk Verification and Repair, Disk Permissions Verification and repair, resetting the SMC, getting rid of old files or ones that take up space. THe only things I haven't done are Resetting the PRAM (not sure if that's even something you can do on a MBP2011), and Re-installing OS X 10.8.
I've heard that Re-Installing OS X 10.8 will solve a lot of the problems (as I have read about people doing this and coming up with heaps of success), but I'm not sure what that would do to my Data (like say delete it all my data). I'm wondering if it will only affect the core operating files or just wipe everything and do a factory install (wow, i think i sounded like a retard there).
please help me, I hate to think that I've screwed things up on my computer already...