I think for the money and the quality the Remington 597 blows the Ruger 10/22 out of the water. the Ruger 10/22 can be a fine rifle with a few more hundred dollars added to it, the Remington is fine right out of the box, and with the Remington Yellow jacket coming out this year, it will be by far way above and beyoud the Ruger
Impossible to answer without knowing what "best" means to you. Price, action, accuracy, etc..
You will need to define "best".
Marlin
Winchester and Browning
Eley Tenex
The gun is a semiautomatic .22 rifle made by Mossberg. Not much of an accessory market for that gun. What are you looking for? sales@countrygunsmith.net
Best to ask a gunsmith for assistance.
.22 lr
The one you can afford.
A Western Field .22 Long Rifle Model M864 is worth between 65-120 dollars on today's market depending on overall condition.
Best left to a professional.
Best left to a gunsmith