Laptop internal DD - which one to buy ?

Hello

I have a laptop ASUS K456U (K456UJ). There are 2 DDs : 1 "turning" DD of 1To and a SSD of 128Giga. When the pc was installed, the 1To DD was used as "data" storage. All the linux working software system and all apps were installed on the 128giga SSD.
It runs under linux mint.

Linux warned me that the 1To DD was going to crash, therefore I have removed it (the pc works much better now - ha ha).

I want to buy a new DD to replace the old one but there are 2 elements for which I do not know what to choose:

parameters of the existing DD:
- HDD: 1 To
- SATA (connexion)
- 2,5"
- 5400 RPM
- 6.0 Gb/s
- Cash memory : I do not know

I have looked to buy a new DD but I do not know what would be best concerning 2 parameters:
- cash memory: what to choose ?
- turning speed: 5400 or 7200 RPM
(I do not mind if it does not turn fast as long as it does not crash). I sometimes add video subtitles and one rare occasion I do CAD stuff, otherwise I access internet, emails, documents, speadsheets, drawings, presentations etc (nothing fantastically demanding).

Here in France there is a shop called LDLC, you can buy online or you can go to the real shop (there is such a shop 50 minutes away from where I live).

https://www.ldlc.com/informatique/pi...45.html?sort=1

I have all these choices (web link above) with different turning speeds and cash.

I will buy 1To, not 2To (the bigger it is, the more things to back-up !!!)

So can someone tell me what turning speed and cash would be best and why (what does it really change ?)

For example, indicated on the "Fiche technique" (technical sheet): for the cash memory (in French: taille du cache): there is 128Mo or 64Mo or 8 Mo or 16 Mo
and for the rotating speed (vitesse de rotation): there is 5400 or 7200rpm

So what to chose ? What does it change ? Which make is better (if one can be considered being better ! ha ha, I guess not these days).

Thanks

Joelle