Depends on any restriction or similar the people with the benefit of the charging order have put on the title.
You could check with the Land Registry as to what they would need on order to register the change to the title.
You will need your title number and can find that here...
http://www.landregisteronline.gov.uk/
Find the appropriate office here (for where the property is)...
http://www1.landregistry.gov.uk/regional/
The process is quite simple, a TR1 (transfer deed) to the Land Registry with and AP1 form and the appropriate fee, should be �40.00. I believe the Land Registry now ask for ID from private individuals (ie not send via a solicitor)
Forms downloadable here...
http://www1.landregistry.gov.uk/publications/? pubtype=1
If on the title has someone got a power of attorney or similar to sign for your mum?
Bear in mind that even if you get your names on then there may be problems selling or remortgaging without paying off the charging order.
A solicitor should be able to do this quite cheaply (I do as not much work involved) and make sure you all get the proper advice.