help with PCMCIA ethernet card

Folk;

I have a two years old Compaq Presario 1201T laptop running Windows ME.
I'm in the process of buying a PCMCIA ethernet card for my box.

The Compaq manual (if it can be called that) only says that I have
one type I,II,III slot. I have no clue about the differences between
types I,II,III.

I have checked a couple of computer stores (Best buy, Comp USA) and
noticed that there are type II 16 & 32 bits version of the ethernet
card for laptops.

The sales folks (mostly kids) tell me that I should buy the 32 bits version
as it defaults to 16 bits if my pcmcia slot only accepts 16 bits signals.

My question to you all is 1st, what are the differences among types I,II,III
and 2nd which pcmcia ethernet card I should buy, 16 or 32 bits.

Any help is appreciated