The normal advice is actually to leave them for much longer than 24hours before you try and interact, more like 2-3 days. So I would leave him alone until he's really properly settled. Moving from the pet shop to a new home is the most stressful thing that happens to a ham really so you need to give them time to adjust.
I'm sorry you had a negative experience with your first ham but please believe me when I say your little ham wasn't horrible, he wasn't mean, he was biting because he was scared. I'm sorry you lost him before you had the chance to learn to trust eachother. With your new little friend remember than slower is better. If you push them too far too fast they will get scared and that is when they bite, it's purely self defence. They are tiny little prey animals and nervous in general. Those from good breeders will have learned to trust humans from a young age, many do not get this experience so getting them to trust you takes time and patience and kindness. If he is lying on his back and screaming this a a very extreme sign that he is terrified. Please leave him alone, step back, turn the lights off in the room even and let him calm down.
Before your hand goes anywhere near your ham give him a tissue with your scent on it (stuff it in your bra or up your sleeve) and ideally ham will take that to make a nest with so your scent is associated with cosy warmth and safety. Sit by the cage and chat softly to them so they get used to you being nearby and the sound of your voice. If they are still hiding from you then they are not ready to be touched.
Introducing your hand should also be done slowly. Have a high value treat in your finger tips and let your hand sit quietly by the door of the cage and let the ham come to you. Don't go to grab them or shove the treat in their face. Once they are completely and totally happy to do this regularly (might take hours, days, a week to build this trust, depends on the ham) then start setting the treat on a flat hand to tempt them into stepping into your hand. Gradually move the treat further from the edge so they have to put their feet on you to get it. Once they are happily standing on your hand THEN and only then can you start picking them up. Always scooping from below and never grabbing from above. If the ham flinches when you move your hand then stop moving your hand. If they have their ears pinned back then they are probably scared, don't move towards them. Ears should be up and alert, whiskers forward and they should be curious and wanting to sniff you.
Sitting in an empty bathtub is a great place to work on this, some hams will be less defensive outside of their cage and if you sit quietly in the tub with them they will get used to being close to you. Use a big cup or a carrier to get them to the tub and leave that in there so they have somewhere to retreat to if they get nervous or over stimulated. These methods are slow and they take patience but the reason you hear of so many hams being bitey or "mean" is just because people don't take the time to learn their body language and understand their behaviour. Taking things at your hamsters pace reduces the chances of pushing them to bite or creating a situation where both you and the hamster are scared of eachother.
I hope you have a better experience with Todd. This forum is very friendly and generally you get quick responses if you have a question so don't be afraid to check if you're not sure about something
the Housing section should be helpful for choosing a new cage, I've attached an image created by forums user SinNyx showing examples of the cages that are suitable but again, if you want advice or help on sourcing a cage just post a thread and we will do our best to get you sorted
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