All of the above; everybody has given you good advice. Out of curiosity, how did you come to choose Ambergris Caye?
The neighborhood you're in is one of the nicest areas south of town. ~ 2.75 miles. Quiet, pretty and safe. There is an organized neighborhood watch. Your resort, Pelican Reef, is very nice, nice staff, beautiful area on the reef. Yes the ladies will be fine, anywhere. Usual cautions. When youre in town, avoid doing stupid things like leaving your purses and valuables unattended, or leaving your golf cart unlocked.
Diane and LoanSum basically said "do yourself a favor take a flight". If you want to save yourself some money flying to the island take a taxi to Municipal Airport for $25 and fly from there. Its less because the Muni doesnt charge the airlines the fees that BZ Int'l does, the savings are passed on to you. Otherwise fly either airline from Int'l. Google Tropic Air, Maya Island you can book flights from either airline at either airport from their websites.
Okay water taxi...25$ taxi ride to the docks. Most of the taxi drivers will take you to the one that's leaving soonest, but ask anyway.... As to the boats themselves...no toilets. Unless you book Tropic Ferry for ~$125USD roundtrip or $75USD oneway, google their website. They pick up at the airport and get you to the island. Their boat has a head, music, rum punch, its large, and it's a pleasant trip. Btw Belize is not Jamaica or Barbados, not much in the way of steel drums...Did I say Tropic Ferry had toilets? I did? good, the others dont...
On the other water taxis you're basically in an enclosed roughly 40' launch on bench seats at the mercy of whatever the weather decides to do, along with however many people they decide to jam aboard. If it's smooth its okay. If its windy, it's going to be choppy and uncomfortable...particularly if you or a member of your party is prone to sea sickness. Did I mention there are no toilets? No? You've just had 3 beers at the airport to celebate arrival and you're on a boat with..no toilets, for 75 minutes...ready to fly yet? I am...
Neither the water taxi or the flights are unsafe, it's more a matter of comfort, convenience and speed. I hope this helps, seriously.