"Well, my computer is being quite slow, which is why I was in Disk Utility in the first place. But I'm not sure if I'm up for cloning my hard drive to an external one, it sounds quite scary!"
Actually, it's not difficult at all.
Do you have an external drive yet?
If not, I'd suggest something like this:
http://www.amazon.com/Syba-Connecla...?ie=UTF8&s=electronics&qid=1253062702&sr=1-22
Then, go to newegg.com, and pick up a "bare" SATA drive that's at least the size of your internal drive.
Then, download CarbonCopyCloner:
http://www.bombich.com/
Use CCC to "clone" your internal drive onto the copy. If there's a lot on the internal it may take a little while.
When that's done, do this:
- Restart
- As soon as you hear the startup sound, hold down the option key and KEEP HOLDING IT DOWN.
- The "Startup Manager" screen will appear.
- You should see both your internal and the external "clone".
- Click on the external (clone) and hit the return/enter key
- The Mac should boot from the external drive (or the "docked drive")
- When you get to the Finder it should look exactly as your internal (that's what a "clone" is all about)
Doing this proves that you have made a "bootable clone" of your internal.
Navigate to Disk Utility on the CLONED DRIVE. Do not make the mistake of launching the copy of DU on the internal drive.
Now, choose the re-partition the internal to ONE partition. YES, THIS WILL ERASE the internal drive. That's what you want to do.
Once that's done, quit DU.
Launch CCC from the external clone, and choose to "re-clone" the external drive BACK TO the internal drive. Again, it will take a while.
When done, reboot. I'd suggest the "option key trick" again, and then "hand pick" the internal so that you know you're booting from it.
Might be a good idea to go to "Startup Disk" in System Preferences and re-designate the internal as the boot drive.
You're now booting from a "cleaned up" internal drive with only one partition.
Keep using CCC to "dupe" the contents of the internal to the backup at regular intervals. You can set up CCC so that it does incremental backups which will go much more quickly.