rimfire central should be renamed rimfire INSANITY!
If anything related to rimfire guns or ammunition appears under the sun it will also appear there a nanosecond later.
So far, all the suggestions are good. In your particular case, I would disassemble, clean everything extremely well, reassemble with great care and attention to torque on the receiver screw. Pay close attention to any marks inside the stock along the barrel channel; could be high spots that need to be relieved. Leave off the barrel band and start shooting 5 shot groups from a rest. Do you have any old carbon paper laying around? Lay some pieces along the channel to see where the barrel is touching to see where you may need to potentially remove some wood. One simple trick is to wrap a piece of electrical tape around the barrel at the receiver to get the barrel up off the wood.
If you want to do something while you have the receiver disassembled, yep, gently stone and polish all the trigger group parts or just replace them with Kidd or Valquartsen parts. Look for the wear marks and clean all that, especially inside the receiver where the bolt handle rides. Get a bolt buffer to help minimize the felt recoil from the bolt slamming against the receiver.
While you're at it, reshape the bolt hold open part so you can have a bolt release by just tugging back on the handle. Very easy and useful modification.
Personally I'm not a fan of the stock sights on a 10/22. Lots of options. The supplied 'rail' with the 10/22 is not well suited to the plethora of aftermarket sight options. For iron sights, there's an active discussion on the RC site about irons. I like Tech Sights because they're economical, sturdy, easy to install and work well in most situations suited for a casual 10/22.
The 10/22 is a great little carbine. Besides the AR15, I don't recall seeing so many aftermarket accessories from so many suppliers. The junk gets weeded out fast. You can quickly and easily drop a grand building a target rifle capable of holding 3/8" or less 5 shot groups all day long. With some careful work and shopping you can probably get close to that kind of accuracy for well under $200 using your stock receiver and parts and doing a lot of the work yourself.
Comfortable shooting positions are a large part of the accuracy equation. Technique is also critically important. If you don't use the front barrel band, you should install a sling stud and get a simple military cotton cloth sling to start with. Is your wife comfortable shooting with the wooden stock on the Ruger? Does it fit her for LOP, comb height, palm swell?
Have fun, enjoy yourself at rimfire central! Really nice group of folks there.
Another avenue to accuracy, I suggest with caution, are the Appleseed events...