In both cases your wallet file (usually named default_wallet) inside the AppData directory will not be deleted.
To be on the safe side, you might simply want to make a backup of (1) your 12/24 word seed mnemonic (inevitable) and/or
(2) the wallet file (located in \Users\YourUserName\AppData\Roaming\Electrum\wallets), accessable through pressing WIN-key + R (to open run-command) then enter: %APPDATA%\Electrum\wallets
wallet file changes usually happen with major version releases such as from 1.x to 2.x and to 3.x. but you should always keep a back up of the seed and back up the wallet file if you are doing a major update.
it is also a good idea to keep track of the change through the change long here: https://github.com/spesmilo/electrum/blob/master/RELEASE-NOTES so that you can be aware of the changes that happened. sometimes updates are not necessary at all. for example they may fix a bug with hardware wallets which you don't even use. but sometimes they may be mandatory such as critical bug in JSON-RPC interface.
Updating to latest version is much advisable but not really a necessary thing unless if theres an issue then update is a must. Even now im using up 3.1.3 and didnt bother to
DL 3.2.3.
Precise answers about op's concern is already answered above i dont know if OP do able to read it up.