Try posting in the Decorating forum.

Be aware that your two year old is two years old for only one year; and so on and so forth. Decorate for the person your child will become. It may sound cold, but Big Bird can only carry them so far.

Or....look for decals that can easily be removed.

Just make it a nice room - a room in which he can grow. My DD has two sons and when the cherry duvet covers and gingham dust ruffles bit the dust a few years ago (she had bought them when she got pregnant, 18 years ago, from either Company Store of Garnet Hill - can't remember which), this time she headed to LL Bean for quilts and I found some ready-made, very heavy ticking dust ruffles. A fresh coat of paint and a new rug remnant, and she was good to go.

You can add whimsy with art. We took pictures from a wonderful reproduction children's book and framed them, and then I bought the most wonderful prints of cats on trains when in Scotland on the Jacobean steam engine. They are a cat family and these are very charming. At almost 15 and 17, they love these pictures from their early years and have no desire to change them. A good bulletin board where a child can pin up awards and other things, is always useful as well.

Stay away from Disney characters and sport teams bedding/decor. One will tire of it very quickly.

We selected duvet covers, curtains and rugs in a basic color scheme (navy and white for one, gray and red for one and peach and aqua for our girl) then got "themed" sheets and art work that went with their interests. Our 7 year old is rockets and stars, 4 year old is vehicles and 2 year old is floral and bikes. Choose a Double bed if they fit in the room, then the kid can take it with them when they are an adult (also way more comfy for the occasional midnight snuggle)

neutral furniture, big enough bed to last at least 10 years, if there's space, a table for playing at at the moment and school work in sone years
neutral flooring (I prefer hard wearing carpet, if you have allergy issues maybe not)
neutral rugs, machine washable
a feature wall (shapes, stripes, wallpaper, decals, etc)
light colours, but not an overload of them. Make it peaceful

For boys of all ages, I absolutely adore madras quilts/duvet covers, and madras has enough color variation that you can change the rest of the decor to reflect your little guy's preferences as he grows. Denim would also be a super cute choice for a baby, as well as a great masculine choice for a teen.

Go with stained wood furniture... Painted wood is feminine (in my mind). Anchor the furniture to the wall, so that he can't open drawers and climb up, only to have the dresser or bookcase fall on him.

I agree with a double/full-size bed. I'm actually a huge fan of wood loft beds (we have a double/full loft, and will get another), where the kiddo can sleep under the loft part when they're young, and move to the top when they're older. Curtains under the loft are a ton of fun for little ones, and as he grows, bean bag chairs or a desk can be put underneath.

...Are those the kinds of ideas you were looking for? Or did I go the wrong direction? lol

My grandsons have old spindle beds that were painted white. They do not have a problem with that. As for anchoring the furniture to the wall, well, it really depends on the furniture. If it's new, lightweight with little wood actually in it, then yes, that is important. In my grandsons' room, they painted and re-used furniture that was old when my in-laws bought it in 1948 for their summer house - heavy as lead! Same for the bookcase - it would take a 200 lb man trying to climb on it to tip it over and it would hold him!

I don't like double beds in children's rooms. My children (and two of my grandchildren) have sleepovers all the time and twin beds are so much easier then. If you can, buy extra long twins like they have in college dorms (bedding is readily available for such).

My grandsons share a room and are lucky that it is quite large (about 18x18). When I replaced the sleep sofa in my library (purchased at Bloomingdales in 1966 for our first apt), it went to their room, so now friends who are sleeping over can sleep in a bed instead of on the floor. Getting that heavy sucker up the stairs was a major challenge!

Link below:
Anchor your furniture, especially in a baby's or toddler's room, please.

How heavy it is, isn't the issue (although lighter furniture is less likely to kill a child), it's the change in the center of gravity when weight is applied past the mid-way point. The change in the center of gravity, when the door is open, is the same reason why people anchor their slide-in ranges (those can also tip, are very heavy, and can result in death if climbed on).