IIRC, approximately 25% of successful candidates end up at colleges other than the college initially selected.
Ther are no bad colleges. It appears that most people who go to Oxford like or love the college which they go to. In any event, it is easy to make friends at other colleges, and it is usual for some tutorials to be taken at other colleges. At college A, a Fellow who is expert in topic X teaches that topic to undergraduates from college B. Meanwhile, undergraduates from college A are taught topic Y by a Fellow of college B.
Go and visit some colleges. Choose one you like the look and feel of. If there is a particular Fellow of that college with whom you would love to study, that's cool, but remember that he or she might leave, retire, take a long sabbatical or parental leave, or whatever. If you get an offer from that college, that's great. If you get an offer from another college, that's also great.
Good luck!
SB (applied to Wadham, went to Wadham, loved it, and also had a fun time being taught at and partying at other colleges).