What are good fcr items?

Looking to up my fcr for my 51 bowzon. Her

Freezing Arrow is kinda slow. Perhaps it’s attack speed? Or fcr?

At any rate-
I saw that some rune words have a particular high cast rate. But uniques have fewer.
Perhaps the deal is to equip charms and rare rings with fcr?

Suggestions?

What you're looking for is attack speed. Unfortunately, IAS (increased attack speed) doesn't spawn on rings or charms.

What bow are you currently using? The attack speed breakpoint that you'll aim for depends on the weapon itself.

Take a look at the first table to help: http://mynthon.net/d2/ama_tables.php

I don’t understand any of those d2 charts.
What does 22/5 or 9/3 mean in the FPA. And what is fpa?
So if I use a

Matriarchal Bow I’m going slower. That’s a shame after pouring al my sec to get the req.

FPA is Frames Per Attack. It's not important to know about that right now. What matters are the numbers on the right: you target the column that's appropriate for the weapon's base speed.

We'll use

Matriarchal Bow as an example. It has a base speed of -10, which is the fastest possible for a bow (as you can see from the chart). Thanks to this speed, you require less IAS to reach your target, which should be breakpoint 75 .

I don't know the other items you're using, but reaching at least 75 IAS as the sum from all of your gear shouldn't be difficult.