Having had all 4 kids terrified of big costumed creatures that they knew had humans inside (yes, my kids also knew the store Santas were fake all along...it's why we discuss that they are stand ins - I literally had kids who would scream if you took them near Santa who now just go "eh" when they seem him...but still avoid the pics

)...I would not plan TS character meals unless you know their 2 and 5 year olds actually like them.
Also, you don't say if they are on
DDP or not, and if so, if it's DxDP, DP, and CSP...if this is all OOP, I would recommend very few sit downs, since 2 and 5 year old boys do NOT sit down, normally...they run and get anxious having to wait on tables, wait for food, wait for checks, etc...
I think Hoop Dee Doo is fine b/c she really wants it and the show will entertain them. After that, I'd tell her dining is REALLY pricey, especially at character buffets, but it can be worth it if the kids can hack the expected waits and process...
If they can hack it, I'd actually recommend T-Rex b/c that restaurant is all boy...getting to dig for dinos before hand, seeing dinos everywhere, etc...and it's not too pricey for what they'd get...
I'd also 2nd the Sanaa and Coral Reef recommendations since they also have entertainment while dining...which might be very important for them...
I'd steer a million miles away from buffets due to price, the need to get up and get plates for each kid and then the parent, the need to time and get good behavior for the pics (and somehow still eat), the possibility of freak outs from either child over characters, etc...