For me, at least, uninstalling and reinstalling are necessary if less pleasing parts of playing Sims games; both Sims 1 and 2.
This may be because I play with a LOT of downloads, maybe because I like to try new things and experiment from time to time with different hacks.
It can be made less unpleasant.
Also Graphical issues may necessitate a reinstall. For me, if I change my graphics card while Sims 2 is installed and/or update the drivers with my AntiVirus software turned on, the game simply does not recognise the new card/drivers and my game will crash or refuse to load. It seems this has been a known issue for some time for many Simmers, but it is the first time it's come to my attention.
So - get ready to reinstall! (Don't forget to backup your downloads and user files - from My Documents - first!)
As Sims 2 is technically now Abandonware (ie no longer supported by EA AT ALL - including Customer Services) it can be downloaded many places on the Net. As always, be careful.
The Ultimate Collection is available here as it was available for 4 years with Origin.
Each EP has a patch. It IS important to install these as you go through, rather than all at once after all the disks are done. Apparently some things are ONLY fixed by a patch and not subsequent EPs.
[ Patches ]
Sita December 13, 2021