Yes, I was trying to not be quite so graphic but Serendipity has touched on the "practicalities".
Also, a body in soil changes the PH and the plants I tend to bury mine with are hardy evergreens in at least a 30cm pot..most I opt for 40cm. There are also a number of factors that effect the time of decomposition but either way, I would not recommend an indoor burial and many houseplants likely would not survive well with a large organic mass in the pot.
I have rat friends who have dug up their rat skulls and varnished them, I quite like that idea but all my bushes in pots are well established now so I leave them be!
I don't personally get upset with the bodies of my pets, just their memory. I have buried ALOT of hamsters and rats though and I quite like the ceremony I go through picking out the pot, the plant and burying them... then the joy of seeing that new life grow from their bodies nourishing them
The legalities on burying pets tends to be more for larger ones like cats and dogs.
I know some members go to a local park or woodland and bury their hamster in a shallow grave. They leave a little memorial there to visit back to.
There are quite a few threads on HC of burial methods that members have posted. I'd recommend browsing them than the open source of facebook