We don't hear about bad copy protecting as much as we used to. It's not that it doesn't exist, but the pervasiveness of services like Steam, Origin, and GOG is making things like this less and less of an issue. For those old games, though, Windows 10 users might experience some trouble, if those games use SecuROM or Safedisc for their copy protection.

Microsoft's Boris Schneider-Johne spoke about this at this year's gamescom. Everything that worked in Windows 7 should work in Windows 10, he says, with a couple very specific situations:

There are just two silly exceptions: antivirus software and stuff that's deeply embedded into the system needs updating – but the developers are on it already – and then there are old games on CD-Rom that have DRM. This DRM stuff is also deeply embedded in your system, and that's where Windows 10 says "sorry, we cannot allow that, because that would be a possible loophole for computer viruses." That's why there are a couple of games from 2003-2008 with Securom, etc. that simply don't run without a no-CD patch or some such. We can just not support that if it's a possible danger for our users.

He goes on to mention that some developers are creating patches for these games and that places like GOG can potentially help. If the DRM providers can update their software, it could be a potential patch for all games using that DRM, but that's unlikely. Schneider-Johne's suggested solutions are the more likely ones.

It's worth noting that this is separate from concerns that Windows 10 could potentially disable pirated software, as this pertains to software that worked by putting its hooks into places in Windows XP and Windows 7 where there simply are no longer places to hook into.

GiantBomb has a pretty extensive list of SecuROM games here, but a list of Safedisc games doesn't seem to be available.