Reboots Desired:
QUARANTINE - For those of you who have never played it, imagine GTAIV mixed with Mad Max. A city where the water was 'treated' with a chemical that turns everyone into a homicidal maniac intent on killing anyone else who was not a homicidal maniac. You're a taxi driver trying to scrape together the credits to get out of the city. I enjoyed having an ejector seat so I could ditch fares I didn't like / were too tough, or catapult them into the enemy as a living missile.
POLICE QUEST - Updated and grittier. More akin to PQ3 (murdering rapist satanists) as opposed to PQ1 (parking tickets and DUIs). Something more like the British show "Waking The Dead".
COVERT ACTION - Espionage game chock-full of minigames. Sid Meier designed it, no? Anyway. Building infiltrations, cryptography, car chases, interrogations, phone taps, alarm circuits, coupled with a Carmen Sandiego-style international hunt for documents, terrorists, and kidnapped scientists. Sweet Jesus it would be awesome even in iOS/Android form due to the extensive use of minigames.
And just to fuck with everyone:
THE ELDER SCROLLS ADVENTURES - I want to play as Cyrus again damnit. Coolest Redguard in existence.
EDIT:
Also, not really a reboot but rather a port, I want ResEvil:Outbreak Files I & II on PC. The first game is damned near 10 years old now - it would surely be easy for even fossil PCs to run and give us all a dose of REAL team survival horror.