what is the appropriate OS for Macbook pro A1211

The highest your machine can go is Mac OS X 10.7.5 (Lion). Apples general requirements (according to link):

• Mac computer with an Intel Core 2 Duo, Core i3, Core i5, Core i7, or Xeon processor
• 2GB of memory
• OS X v10.6.6 or later (v10.6.8 recommended)
• 7GB of available space
• Some features require an Apple ID; terms apply.
• Some features require a compatible Internet service provider; fees may apply.

I would say with memory I go for at very least 4GB-8GB (I believe this machine can only handle 4GB). Also if your not already on this version backup before updating.

You have a Late-2006 MacBook Pro that was discontinued in June 2007. The Model ID is 2,2.

You can purchase Snow Leopard through the Apple Store:Mac OS X 10.6 Snow Leopard - Apple Store (U.S.). The price is $19.99 plus tax. You will be sent physical media by mail after placing your order.

After you install Snow Leopard you will have to download and install the Mac OS X 10.6.8 Update Combo v1.1 to update Snow Leopard to 10.6.8 and give you access to the App Store.

Snow Leopard General Requirements

1. Mac computer with an Intel processor

2. 1GB of memory

3. 5GB of available disk space

4. DVD drive for installation

5. Some features require a compatible Internet service provider;

fees may apply.

6. Some features require Apple’s iCloud services; fees and

terms apply.

Although this would be the best running OS for your model, you can upgrade to OS X Lion which is as far as you can go on such old hardware.

Upgrading to Lion

You can purchase Lion at the Online Apple Store. The cost is $19.99 (as it was before) plus tax. It's a download. You will get an email containing a redemption code that you then use to download Lion at the Mac App Store. Save a copy of that installer to your Downloads folder because the installer deletes itself at the end of the installation.

Lion System Requirements

1. Mac computer with an Intel Core 2 Duo, Core i3, Core i5, Core i7,

or Xeon processor

2. 2GB of memory

3. OS X v10.6.6 or later (v10.6.8 recommended)

4. 7GB of available space

5. Some features require an Apple ID; terms apply.

Are my applications compatible? See App Compatibility Table - RoaringApps.

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