movieflick, what I'd do if I were you is buy your mask (because fit is critical), snorkel (because they'll make you have one), fins and booties before your class. If you want my two cents' worth, don't spring for the expensive split fins at first. You can buy very cheap blade fins for your class (that's what my husband did) and then decide a) if you're going to continue doing this, and b) if you need anything more than what you have for your beginning dives.
As far as regulators go, according to the VERY experienced and multiply credentialled regulator repair guy at our LDS, who's been diving for over 50 years, almost all regulators are well made and reliable these days. There are many regulators that perform quite well and are not ridiculously expensive, and the ones with all the bells and whistles remind me of the stereo equipment you can buy that your oscilloscope will love, but that you will never be able to tell from something far cheaper. If you aren't ice diving, or going to 300 feet, or a mile back in a cave, many mid-level regulators will give you years of service at a manageable price.
As far as BCs go, it's very much a matter of personal preference what you dive. Whatever you buy has to FIT you well, and you have to like diving in it. Your shop should have equipment for you to use for your open water class, most likely a jacket-style BC, which will give you an introduction to that type of gear. You ought to be able to rent a back-inflate somewhere in your area, to try that. You may not be able to rent, but might be able to borrow a backplate/wing setup, if you become interested in looking into that option. The important thing again is that it must FIT correctly and be comfortable in the water, and easy for you to use.