IllBleed Dreamcast (Real console recommended)
Still Life Xbox (Real Console only)
Call of Cthulhu: Dark Corners of the Earth Xbox (Real Console only)
The Thing Dreamcast/Xbox (Real console recommended/Real console only) that might of had a PS2 release aswell
A lot of the SCUMMVM games, a lot of crime solving games here (I like the Elvira games myself) you should be good to go with these
SCUMMVM also has games like 7th Guest & Beneath a Steel Sky
PSX you should be ok with if you use some of the older emulators (Not sure how good ePSXe will run on an older setup)
N64 (not even 64bit) you will struggle with mostly, some games via certain emulators should run just fine though
Saturn I don't think so, but SSF is worth a try (You may end up using an older version though, but if it works well it is worth using)
GBA SNES and under you are fine
GG Megadrive/Genesis and under you are fine
Sega/Mega CD you should be ok with as well
Sega 32X You might start to struggle with
Sega/Mega CD-32X, I don't think so but worth trying