Upgrade to Snow Leopard on Macbook 4,1

The normal installation mode for Mac OS X 10.6 Snow Leopard is an upgrade install, meaning no data or application of yours gets deleted, but it is always recommended to at least make a backup to an external HDD via Time Machine or CarbonCopyCloner (version 3.4.7 is still free and available for download here and works with Mac OS X 10.6 Snow Leopard, Mac OS X 10.7 Lion and OS X 10.8 Mountain Lion) or SuperDuper! before doing such a task, in case something goes wrong.

As for upgrading RAM, yes, the battery needs to be removed, which should be an easy task on a 2008 white MacBook.

Hi,

the Macbook white 4,1 can use up to 6 GB of RAM.

You can upgrade to SL using a retail (white) disc.
It will no work will a grey disc which came with another model of Mac.

You can also upgrade to Lion (10.7.5) which is the maximum OS for that model.
(to buy Lion see Apple Store).

How to upgrade the RAM ? See here : http://support.apple.com/kb/HT1651?viewlocale=en_US&locale=en_US

You don't lose anything when you upgrade the OS : only the OS will change, all your apps, settings, and data will remain unchanged.

Yes, you do need to do a full backup (do a clone) just in case something went wrong when installing.
(and you need a full backup anyway : Time Machine and/or a clone).

If you have a white SL retail disc, it is 10.6.3.
So after you have installed, download an apply the 10.6.8 combo update.
Then run Software Updates do get all other available updates.

You can NOT install Mavericks on that machine : the maximum OS is Lion 10.7.5.

You would need to boot from the SL DVD only I you wished to first erase your internal drive to then perform a "clean" install (all your apps, settings and data would be lost).

You don't need to boot from the SL DVD (C key) to upgrade.

Take a look at this : http://macs.about.com/od/snowleopardmacosx106/ss/upgradeinstall.htm

Snow Leopard will run fine on that Mac with 4 GB of RAM.