Music

Hey Megan. Personally I think it should be music that both you and your fiancée want to hear for your special day!

Haven't really thought about the music during dinner but the music for our cocktail hour will be comprised of singers and bands my FH and I have seen in concert together We may omit some of the "louder" bands, but will still have a great mix/variety of tunes

As mentioned, most good DJs can read the room and tell what type of music the crowd will like. I'd get them an idea of the type of music you like and your do not play list.

If you are going with a company I'd be careful, some companies just hire teens and college kids for the wedding season.
I have friends who did djing for bulk hire companies that enjoyed what they did and took it seriously while employed. I've also been in a wedding party where the DJ that was provided only played the music they felt like and told the best man this is what I like. The music was all 2010- present top 40; the bride and groom requested alternative, indie and golden oldies.

I personally would give the DJ a few songs (like three per genre of choice) and let them figure out the rest.

It depends on the vibe you want to go for. We were in a country club so we asked for jazz and coffee house music during cocktail hour and then 80s/90s slow jams/R&B for dinner. We didn't want something loud where people would have to yell over each other just to talk. We also avoided current Top 40 because we didn't want our wedding to feel like a prom.