Yes, going to a good university matters.
Firstly, the education you receive it typically better at better institutions. Granted, there is likely relatively little difference in the top 5-10 for a given subject, and these will vary year on year, however there is a big gap between the top and the bottom. I had a friend who studied physics when two universities were merging and one class covered in the first 6 months what the second class covered in the WHOLE YEAR. The less able class had to do different tests for the rest of their course as they just didn't have the subject knowledge.
Secondly, given 40-50% have a degree these days, where the degree is from is counting more and more, plus you will also find that some universities have employer links which can benefit you after graduation. People will look at degrees from places they know/rate more favourably than those they don't it's as simple as that.
I would note though, that provided you're in a "decent" university, there isn't that much difference between them (bar Oxbridge debatably).
Also first class honours are likely to get you attention no matter where they're from, so how well you do at your degree is obviously the most important.