Hell is just the eternal punishment of god and the reason Satan wants people to go there is one of several reasons
He doesn't want more people to go to heaven
He hates humans with an unlimited passion
and a few probably many others that i forgot
Seriously, unless I missed a few verses when I checked through 'em, the
only motivation for Satan that is explicitly stated in the bible was doing freaking YWHW's command in a couple of cases. That was it. Other than that, it deceived but its reason for deceiving was never stated.
And as for hell, it is
magnificently ill described. There's some bits on fire, but the nature, extent, and so forth, insofar as I noticed, was unmentioned. There's also contradictory bits (like in that revelations bit -- 21 or 22 puts the sinners and whatnot outside the city, not in hell, alongside a couple other oddities.), parts that ascribe fire only to a specific group (sodom, gomorrah, and surrounding cities) or specifically to the rebellious angels and false prophets, with no mention made of others. I'm also seeing it alternately described as eternal darkness, plain destruction, or simple disconnection from YWHW's presence. It's a bit of a mess.
Also, no, there's no mention as to its size. Some mention of it actually being on earth, iirc.
And, interestingly enough, the bible apparently explicitly states the existence of Hades. What's up with that? Just shanghaiing another religion's word?