Can anyone tell me what the toilet situation is like when u are ashore? There must be public one's but are they for disabled people in wheelchair's and whats situation like if u go in hotels or Bar's? Peter

You cannot get off a ship in St Petersburg without a visa which you will not be able to get as a ship is not considered a residence. The o nly way is to book an excursion with the ship you are travelling on and that covers you for your visa.

Sorry but that is incorrect. You can apply for and obtain a visa if you will be staying on a cruise ship, you have to obtain an invitation to visit the country through an agency who will provide you with a Russian address and the invitation. .. Once you have an invitation you can apply for a visa, you don't have to provide an address in Russia for the Visa. Though the whole procedure can take weeks.

But the price and often hassle of the visa application is probably not worth it just for a couple of days stay.
better to book tours with a local tour company or the ships own tours.