I'll answer your second question first. I would definitely suggest a full-time course over a distance learning course, as long as you have both the time and money to spare. I did distance learning because I couldn't spare the time to study full-time, and although it's not impossible, it's certainly difficult. Having said that, though, a few people have commented that they prefer to work at their own pace, and that distance learning suits them better - I think this is a minority, but there's an element of personal preference involved.
As for Oxford vs Bristol - if you decide to study full-time then your choice has already been made, because Bristol don't do a full-time course. If you go for distance learning, then I can personally recommend Bristol, but from what I've read on here you won't go wrong with Oxford either, so visit both of them and go with whichever you like the best. Don't worry too much about comparing the numbers - it is you who will pass or fail the exams, not the school. I don't know exactly where either school derives their numbers from, but it's possible that Oxford's numbers include full-time and integrated students, whereas Bristol's won't, so you're not comparing like for like in any case.
Good luck,
FFF
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