What will Time machine do after a complete uninstal of OSX?

Question

If I completly remove OSX from the machine, format the drive, then do a brand new install of OSX, on the new install, if I hook up my Time Machine HDD and run time machine I can re-load specific folders from my old (1st) install?
Also I used bootcamp to create a second partion that runs windows.  Will that partition remain intacted if I re-install OSX?  Will only the OSX partition be formatted?

Answer 1

What you want to do is make yourself a "hold the option key" bootable clone.
1: Get yourself another external powered hard drive.
Disconnect any other drive, don't want to format them by accident.
2: Open Disk Utility in your Applications > Utilities folder
3: Select the new external drive makers name and click Erase > Format HFS+ Journaled (default setting) click Security Option > Zero all Data from the drop down menu that appears. Now wait, it could take a hour or so.
The "Zero" is a extra step to map off potential bad sectors on the drive before data is laid, I do this to all my new drives once, makes the data more reliable, after that a regular Erase is sufficient unless you want to scrub the drive of any trace of data.
4: Once finished you'll have a ready HFS+Journaled external hard drive to clone to.
5: Download the free to use (donations accepted) Carbon Copy Cloner here:
http://www.bombich.com/
6: The default setting to clone one drive to another should be fine for cloning to a blank drive the first time (it takes awhile), it's just later on that CCC offers a high amount of customized backup features when you update the clone. You will need to learn to understand what will happen when you update your clone. (files that changed will be archived on the same drive for instance) For now you can just leave things be and clone A to B.
7: Once that's finished, open Disk Utility and Repair Permissions on both drives, there will be a long list of things fixed and if you do it again the same list, it's ok to ignore it.
https://support.apple.com/kb/ts1448
8: Now you can experiment and hold the option key and boot from the external drive. You will notice you can access the files on your internal drive.
Check out your clone and make sure your happy because later on when you erase your internal drive from Disk Utility (either option booted from the clone or hold c booted off the OS X installer disk) it's going to contain your old system in it's entirety.
9: Now hold c and boot off the OS X installer disk and use Disk Utility to erase your OS X partition and reinstall OS X like you want. When you go through setup use the same hard drive name and user name as before (different password) this way when you reboot and drag & drop copy the contents of your user folders from the old clone into the user folders of your new boot configuration your iTunes playlists and other "references" (pathnames) to your files remains intact
You can cherry pick user files from the clone this way, cleaning house essentially, with only what you want on the new internal boot drive configuration. But before you do that, make sure you Software Update fully and install your program from fresh sources to make sure they are pristine. Doing Software Update and installing programs first before returning files optimizes OS and programs so they are placed on the faster part of the drive near the front.
10: Once your up on your new drive good, clone that to yet another hard drive, using the same methods above and you'll have a bootable backup.
Note: TimeMachine + Migration or Setup Assistant for restoring is indiscriminate, it just copies. And TimeMachine drives are not bootable.