Mike, 

I’m so sorry for your loss.

Good thinking about her Facebook account.  Yes, you can download a complete copy of everything in her account.  Here are the Facebook instructions:

1. Click  at the top right of any Facebook page and selectAccount Settings
2. Click General in the left-hand column
3. Click on “Download a copy of your Facebook data”
4. Click Start My Archive

You can read more on Facebook’s Help page on Downloading Account Data

Then you can either delete her account, or Memorialize it.

You might want to consider ‘Memorializing’ her account.  That way people can still leave messages or post pictures on her timeline in her memory.  Here’s what Facebook says about Memorialized accounts:

When a person passes away, we memorialize their account to protect their privacy. Here are some of the key features of memorialized accounts:

• No one can log into a memorialized account and no new friends can be accepted
• Depending on the privacy settings of the deceased person’s account, friends can share memories on the memorialized timeline
• Anyone can send private messages to the deceased person
• Content the deceased person shared (ex: photos, posts) remains on Facebook and is visible to the audience it was shared with
• Memorialized timelines don’t appear in People You May Know and other suggestions

Here are the instructions for Deactivating, Deleting, or Memorializing a Facebook Account.

If you want to print everything she shared on her timeline, you might want to look at LikeBooks.  I’ve never used it so can’t vouch, but I have used similar services for Blogs, and it is a great thing to have a printed book of those memories.