When it comes to sliding, many people say otangs and abec 11 and stuff... They are extremely overrated (except for the newer otangs). Some good wheels are Cult, Vault, volante, Cadillac, seismic, these (can be expensive) and many more.. Do some good research and you will find a wheel that suits you
Chicken nuts
Spitfire wheels look the best....
It depends on the size of the wheels. I'd recommend Tunnel wheels.
purple orangutans are good
Yes, just swap your bearings from skate wheels to longboard wheels, its all the same.
There are many ways, like putting duct tape arount them. But if you wish to slide or do complex turns and tricks, you are just better off buying an extra set of the same wheels.
Your not suppose to do tricks on a long board the just for going fast.
A longboard or hamboard.
Wheels on skateboard can be as little as 50mm and go as big as 70mm (longboard wheels) and the softness rating verys. Smaller wheels are better for flip tricks, while bigger wheels are better for ramps and cursing . Harder wheels are better for tricks, while softer wheels are better for multi terrain cursing. What you want to do is figure out what you want to do on your skateboard (your skate style), from there you can choose the wheels that works best for you. Note for bigger wheels you are going to put risers on your board to prevent wheel bite.
It makes it slightly harder to do tricks but it will help keep the board stable. I recommend getting some rises to help increase your pop of the board
depending on the sises of the wheels will shrink
depends on how used and what brand and model of wheels.