What are the quickest stickers to unlock in Rare Replay?

If you have played any of the 360 games before (Banjo, Perfect Dark, Viva Pinata), Simply launching them once will sync up any achievements you have and give you stickers. As the 360 games' stickers are achievement based.

Also, most of the stickers you get just for playing the game without any extra effort needed. Jetpac, for example, although might take a short while, is possible to get nearly all stickers in one session. Most of the older games are set up this way, just build up score or play through the game for a bit to get the stickers. You can enable cheats like infinite lives in the game's option menu to make this even easier.

Any of the Snapshots are a great fast way to get 1-2 stickers as well.

There's a few ways I've found to get stamps fairly quickly / easily:

1. Almost all of the games will give you one stamp just for starting it up, so you can boot them up one-by-one. The exceptions are a handful of games that just list stamps as based on your Gamerscore. Usually you'll get a stamp after you get your first one or two in-game achievements; but that won't be until you get some measurable progress in the game.

2. Older games allow you to use cheat codes. If you activate all the various cheats codes from the menu (varies by game but typically things like no time limit, infinite lives, rewind etc.) then you can "easily" beat nearly all the games. I say "easily" in quotation marks because several of the games may still take a long time to beat the main game and even longer to get every achievement.

3. Play some snapshots. Each of the snapshots is worth a stamp. Usually the first two are pretty easy, the third is moderate, the fourth is hard and the fifth is really hard. If you're courageous, you can play the snapshot playlists; you get 3 'lives' to beat 5 snapshots in a row following a particular theme. When you use the playlist, you'll get stamps for any individual snapshots you haven't already beaten as well as a final stamp for beating the whole set. (It feels pretty satisfying to get 6 stamps all at once!)

4. Play "Conker's Bad Fur Day" Multiplayer Matches. There are about 6 or 7 stamps up for grabs here, but technically this is more of an "easy" source of stamps than "quick." Conker's Bad Fur day has a ton of multiplayer game modes, and each one will net you a stamp for finishing 5 rounds of each mode. You don't have to win, you don't even have to have friends[1]. You can make it go a little faster by setting the minimum time or victory conditions in the match options. (e.g. a 1 minute game or 1 point to win.)

5. Play your favorites. Given that a lot of people are picking up this title for nostalgia, there's a good chance you've played at least some of these games before. Because you know them you'll probably be a little quicker at beating them, even if they aren't objectively the "fastest" in other ways.

[1] - Why don't you have friends? That's so sad...