Car batteries have thin plates that can discharge high amperage(200 amps) for a short time, if they are discharged too much they tend to not fully recharge, so over time if drained to say 50% and then recharged they would last only a few years, instead of the average 5-7 years.
Deep cycle batteries have thicker plates, so they can not discharge high amps quickly, usually they will start an engine(100amps), just don't crank quite as fast.
These are made to be drained down to 10% and then recharged, hence the "deep cycle" name.
These would be best for a winch which doesn't need a high amp output(under 100amps), but steady amps for a longer period.
The isolator to use is based on the alternator amps, 60amps, 90amps, 120amps, isolator is only used for recharging two batteries without having a direct connection between the batteries during drains on the batteries.
The gauge of wire to use is based on amps and length, so longer distance requires larger wire