I like 

1,6, 16,17.

Sorry can't deceide between 27 or 33.

One of the butterflies, as well as #17 (the waterfall).  These will likely be universally liked.  

The rest would depend on the context, which you and your colleagues know best: what type of work you do (and how that fits in; e.g., relaxing or energizing); what type of office you have (including color of the walls: warm/cold, etc.); what ideas people like or dislike (e.g., new and exploratory vs. traditional and ageless, etc.), and others.

OK, after much review, I have come up with a few ideas/suggestions.  Foremost in my mind was that these photos are to be displayed in your office/workplace.  So, here's some thoughts...

• I love #5 (turquoise lizard on rust-colored lichen-covered rock), and would have this one in my office; no problem .  However, some folks may have an aversion to reptiles.  Your call.
• If you are looking for some groupings, then #3 & #4, of the two butterflies, may be OK.  Also, if you are thinking of using the waterfalls, then #6 & #13 would be a good pair, or else #17 & 18.
• The giraffe (#7) is very cool, but I would say no, just because of the pavement.  The iceberg field is nice (#16), but I'm not sure how big of a hit it will be, as it is somewhat stark.  The puffin (#31 & #35) is also really cool, however, the fish sticking out of its mouth may cause an issue with some folks.  The mud holes (#10 & #11) would make a nice pairing, but I think they are just a bit bland on the color scheme.

So, after having said all of that, and with all the considerations, here are the ones that I would recommend:

• #05 - The turquoise lizard on a rust-colored lichen-covered rock
• #09 - The cool house wall shot
• #19 - The overhead of the waterfall, with sunlight casting an aura.
• #22 - The Monarch butterflies feeding (cool colors)
• #26 - The white flower with dew drops
• #27 - The stand of trees (very cool shot)
• #32 - The seals on an iceberg
• #33 - The white flowering plants (remove the date; bottom right)

I apologize that my suggestions are more than five, but I leave the narrowing of my suggestions to you.  Do well.

#3,4,7,8,and 12

Thanks! These are some of my (near) favs too... :-)

The 3rd, 4th, 5th (or 7th) 6th and 8th are my favs :)