Hi :)
You can't install like TS3 - with disks and downloads. It's Either Or.
New computers require new setting for the Computer to run TS2 - both the disks and the TS2UC
There are So many tutorials out there to help you set up the game. So many mods to help it run - I don't know where to start now but I'll link you to:
https://www.simsnetwork.com/tools/graphics-rules-maker
https://simlili.tumblr.com/post/146373494212
https://modthesims.info/download.php?t=569585
https://modthesims.info/t/500523
https://simsvip.com/2014/07/20/the-sims-2-ultimate-collection-increase-resolution-guide/
https://pleasantsims.com/sims-2-mods/
I hope it helps. :)