You can look it up on gov.uk, and save the solicitor's interview to make best use of their expertise once you have decided what you want.
We have always been tenants in common. On either death the house automatically goes to the other 'tenant', and one can't do anything without the involvement of the other.
The usual reason for being 'joint tenants' is if one wants to will their portion away from the other tenant. This usually happens in second marriages where each wants to leave their portion to their children.
I would consider whether there is any reason that you chose to be 'joint tenants' in the first place, and if that still applies. If not, then being 'tenants in common' is usually considered a good step, but that is the point to take legal advice (you don't say who 'advised' you and why you sought their advice)