I thought it might be helpful if I explained the methods I use to connect together families and generally carry out my research from home.
Two sources are key to working out families in the 19th Century.
FreeBMD has almost complete coverage of the period when civil registration of Births, Marriages and Deaths became mandatory in July 1837 right through the rest of the century.
This data gives event type, name, registration district and quarter of year. As with any transcription project, there are errors (not many when one considers how many times this data has been transcribed, as the FreeBMD volunteers are working from an Index created by Civil Servants in the distant past).
Provided a search yields less than 3,000 entries, that search can be downloaded and with the right data handling skills, matched with existing data so that only 'new' events are added.
I've done a lot of work as a volunteer on this project and their data management processes are excellent.
Ancestry.com is an expensive subscription service (priced in US Dollars, so exchange rates matter), but it does provide a fantastic set of data. It's especially useful for England and Wales Censuses from 1841 to 1901 (they do not yet have the 1911 Census). Beware though that indexing is sometimes erroneous. Many names are mis-spelled or misread and it's always necessary to read the image of the Census page to be sure. You have to use some creative methods to find people whom you believe should be present in a Census, but whose name does not appear correctly. Fortunately their search methods allow this (can't find surname, look for a forename + date of birth + place of birth combination).
There is a UK subsidiary of Ancestry, but my impression is that this provides a more limited service, though I have not checked that recently.
I have also worked out methods to capture index listings to speed up the process of extracting relevant data and matching it to existing data. It's always necessary to create your own transcription, however, which is time-consuming.
I have found that with the two sets of data, it's possible to account for 80%+ of events with a high degree of certainty, provided you are using a recording system that allows events to be recorded before people are identified. No commercially available software does this!
So, I have built my own.
But, there are still situations where the only answer is to find a matching baptismal record (which get rarer into the later part of the century) or buy a Birth Certificate from General Register Office (GRO) - Births, Deaths and Marriages registration
It also has access to Ontario Birth, Marriage and Death records (and for some other provinces too) where these have survived and these almost always have information that helps connect events with families and extend knowledge of families. It's not uncommon for a Death record to name both parents, which is sometimes especially helpful in identifying a person who has emigrated from England or Wales
This gets harder! IGI gives outline data only and Parish Registers often contain extra notes which are sometimes vital to work out which family a person belongs to. IGI uses an import / export format called GEDCOM, which I have yet to understand enough to use it to add data to my system.
The bottom line is: you have to look at Parish Registers to be sure about anything. Many are filmed and these films are often available in public libraries (and always in Church of Latter Day Saints libraries); but the film quality is often poor - in which case, a visit to the appropriate library in the UK is essential.