I'd definitely go for the cheaper one. $40,000 is a lot to pay, especially when you're looking at grad school in the future. Honestly, most on-line degrees, if they're attached to a brick and mortar school, don't have the words "on-line" anywhere on the transcript.
My RN-BSN required some clinical hours, others don't. Mine weren't hugely inconvenient, but I would have preferred to skip them. Some in my class who wanted to look at jobs in other areas found that it gave them an "in" to finding a job in a new unit.
I don't think the ranking would hugely matter in your grad school quest. However, I'm not the best one to ask; if there's a particular one you like, it might be a good idea to call their admissions people and ask. I think, in general, it wouldn't matter.
Other things grad schools look at is experience, references, ability to write, certifications (like Critical Care, etc.) and interviews. Some require the GRE--some don't if you have a high GPA. I'm currently working on my masters through a local school and really enjoy the work--so far
, but I planned on attending the one I am at, so I didn't look too far afield.