It's true pywallet can perform search on storage drive. But Bitcoin Core use password in order to encrypt wallet.dat file. So you still need to specify the password/passphrase.

Why do you want to use pywallet as first step?

To your first question: how can someone give you an answer if you don't say what OS was used?

For Windows if copied with File Explorer across different volumes:

• the modification time stays the same as the source file
• the creation time of the new file is the time when the file was copied (not displayed by default)

To your second question: pywallet is a known tool if you download it from its known and reputed sources. But again, why pywallet as first step before you tried to open your wallet files in Bitcoin Core?

Make multiple backup copies of your wallet files, so that you can't ever loose the original files. You only work on copies of copies. Document any step, so you don't loose track or confuse yourself.

What is your prefered OS?

This is what I would do if I don't have Bitcoin Core. Download from bitcoincore.org and verify it's genuine.

Open Bitcoin Core and set it up as a pruned node, the amount for the blockchain doesn't need to be large, you can stick to the default of 2, 5 or 20GB (forgot what the default is, my nodes aren't pruned). When it start to sync, take your device offline to interrupt blockchain download temporarily.

Now load all your wallet files into your Bitcoin Core node. When all wallet files are loaded, you can proceed with syncing the blockchain. This can take a while to finish, maybe a few days. If you need to interrupt the sync process make sure to always shutdown Bitcoin Core cleanly!

When you restart Bitcoin Core it should reload all your wallets and continue to sync where you left.

When the blockchain sync has finished, see if you have coins in your wallets. You can switch from wallet to wallet by selecting the wallet with the dropdown menu in the upper right corner of the Core window.

Be careful when downloading random sources, just the one posted by AndrewWeb above. we don't know if it's safe to use but if you have a spare PC or laptop, make sure you run it offline and don't connect it to the internet if this involves importing a wallet file, and don't forget to format the PC once you've done something.

Actually, you don't need them if your purpose is just to dump keys from wallet.dat file. Pywallet should able to help you dumping these keys with your passphrase.

Be careful when downloading random sources, just the one posted by AndrewWeb above. we don't know if it's safe to use but if you have a spare PC or laptop, make sure you run it offline and don't connect it to the internet if this involves importing a wallet file, and don't forget to format the PC once you've done something.

Actually, you don't need them if your purpose is just to dump keys from wallet.dat file. Pywallet should able to help you dumping these keys with your passphrase.

https://bitcoin.org/en/release/v0.7.2

This was hosted in sourceforge site which is deprecated so im not sure where to find this now. The release notes:

https://github.com/bitcoin/bitcoin/blob/master/doc/release-notes/release-notes-0.7.2.md

The oldest versions I can find is this (Bitcoin Core v0.10.0 oldest):

https://github.com/bitcoin/bitcoin/releases?page=6

Why do you need such an old version anyway?

To find dat files, are you using linux or windows? Just search on the search tab with this: "*.dat"