If you only have one day, recognize you probably can't do everything you would normally do with more time. Although Universal has many great attractions, the undisputed crown jewel is The Wizarding World of Harry Potter. Even if you aren't a fan of the books/movies, the Harry Potter areas cannot be missed. The issue, though is the HP areas are split between the two parks. So, park hopper tickets are necessary. An extra benefit to having hoppers though is you have access to the Hogwarts Express that runs between the HP areas (both HP areas are in the back of their respective parks, so that saves a lot of walking and time).
Like you said, it will probably be too cold for the water rides, so that (plus not being interested in Hulk and Dueling Dragons) will make it easier to get through Islands of Adventure quicker. One tour option would be to start in IoA (stop to ride Spider-Man or check out the Dr. Seuss area) and visit Hogsmead. Browse the shops, get a butter beer, eat at 3 Broomsticks, Ride Forbidden Journey, and then take the Hogwarts Express over to Diagon Alley in the Studios park. Ride Gringotts, get some ice cream, watch the wizards using their wands, (if you skipped 3 Broomsticks) eat at Leaky Cauldron, throughly explore the area (so many details to be seen), then head out of Diagon Alley into London. Then make a loop around the park and ride/watch what interests you.
If you want help figuring out a plan, just let us know which rides, shows, and restaurants you want to visit. A descriptor (must see, would like to see, only if there is time, etc.) would be great too. We can try our best to make sure you get the most out of your day at Universal.
Edited to add: I heard Halloween Horror Nights will extend a few days further into November this year, so if you are into haunted houses, I strongly recommend you consider going. Also, that just reminded me, your tour plan will need to take into consideration that the Studios park closes at 5:00 on
HHN days (IOA stays open a couple of hours later). So, that might affect where you start and stop your tour.