They each behave somewhat differently:
Entangle:
You save when it's cast. You save each round on the caster's turn. If you failed a save, you need to make a Str/Escape Artist check to break out. If you're already free on your round, you can move through without a roll, albeit at half speed. This one's pretty nasty because if you are stuck, you need to make a Str/EA check as a full-round action, and then make your save on the caster's turn in able to move next round.
If you run the numbers on a standard MM orc, against DC 14, it will only make both rolls about 7% of the time, assuming it fails it's first save. This spell is ridiculously good for a 1st level spell.
Web:
You only roll a Reflex save when the spell is cast. If you fail, you're stuck. If you're stuck, you need to roll a Str/EA check to break free. Once you're free, you need to roll Str/EA checks to be able to move at all. You could be stuck a long time without a good Str or EA check.
EBT:
When the spell is cast, anyone in the area must make a grapple check or be grappled and take damage. If you enter the area, you must make a check or be grappled and take damage. On your round, you can roll a grapple check as a standard action to break free. If you fail the check, you don't take damage. If you succeed, you're free. On your round, if you're free, you can move through the area at half speed. On the caster's turn, the tentacles grapple attempt to grapple anyone in the area. Each successful check grapples the creature and deals damage.