Leave the tails on. There is no need to dock them. Short tails may be due to docking or due to short tail genetics (recessive). See Piglet Interventions here:
http://sugarmtnfarm.com/2007/02/01/p...interventions/
At eight weeks old they are ready to wean. The easiest way is generally to leave the piglets where they are and wean the sow away by two strong fences with electric. Then keep the piglets happy with food, water, dry bedding and shelter from the sun and rain. Add a little molasses to the water to make it sweet so they'll drink more.
In three days the sow should debag. Then at seven days she should be ready to rebreed if you want to do that. If not, then bring her back up to finish by feeding her well and take her to butcher. She should be delicious with big cuts.
I would deworm them all given they are unknowns. Observe withdrawal times.
At four months you will likely see breeding activity in the piglets but the gilt (female) should not take unless she is a Lolita (early breeder). Most females breed at eight months. Lolitas at six but unusual. To be safe you can slaughter her at four months as a roaster, or the two males as roasters, leaving the other(s) to finish to about 250 lbs live weight.
With unknown genetics there is the possibility of boar taint if you don't castrate. You can reduce that chance by doing a number of things such as:
1) Eat the boars early before they hit puberty as roasters.
2) Eat her early so they aren't around a female.
3) Keep them on pasture so they have a high fiber diet.
4) Do managed rotational grazing - very easy - thus they aren't sitting around eating and inhaling their manure.
You can do multiples of the above to optimize your chances of not getting boar taint. See:
http://www.google.com/search?q=site:...farm.com+taint
The simplest diet is simply commercial hog feed which you'll find at Tractor Supply or your local feed store. Feed them in the evenings to maximize their use of pasture. Pasture will lower your feed bill and reduce the chances of taint as well as improving the flavor and quality of the meat.
At six months (four months from now) the piglets should be ready for butcher.
The simplest thing to do is to sell them all now and avoid all of the above. Depends on if you wan an adventure.
Have fun,
-Walter