Danny,
The steeper seat tube angle makes you less stable, but one thing to think of is that triathlons tend to have fewer high-speed corners than road races, so it doesn't matter so much. Also, there are numerous articles showing that steeper seat tubes resulted in the same power output with the same quadriceps activation but lower hamstring activation - leaving you more energy for your run. (No I can't cite it, it's at work, but try
google scholar). Most female cyclists I know prefer steeper seat tubes for comfort.
Beki,
1. Cleats don't cause you mishaps. Forgetting to pedal causes you mishaps. The bikeshop will set you up on an indoor trainer. Practise clipping and unclipping with both feet at this stage and you won't have a problem. If you want to do triathlons, the shop will recommend one-strap shoes. I'll recommend a two-strap shoe (no ratchets or anything). During your race, you have the front strap loose, so you can get your feet in quick, and then once you're on the bike you can tighten it as needed. They'll be much more comfortable for general riding though.
2. If you have small hands (like I do) then women's specific handlebars and brake levers are worth paying a little more for. I've never had them, but I really have to reach for the brakes, and when I wear full-finger gloves in winter, it gets pretty hard to reach.
3. You absolutely must get a women's specific saddle. Most bike shops will switch the saddle for no extra cost. Women's sit-bones are too far apart for a mens saddle.
4. Get a hard saddle. It hurts more at first, but it keeps the pressure on the bones. If you get a soft cushy saddle, then you sink into it, so you end up with pressure on the soft tissue, which is really not good.
5. Don't buy a bike with Shimano Sora componentry. If you're really pushing the budget get tiagra. Otherwise go for 105 or Ultegra. Or Campagnolo equivalent, but then you end up paying way more for something that makes so much noise when you freewheel, you'll be embarrassed...
6. If the bike shop wants to adjust your fit buy just giving you a shorter headstem (pushes the handlebars forwards or back) make sure it's not smaller than about 100mm. If you start getting down to 90mm, you probably just need a smaller frame.
7. Make sure you get quotes from multiple bike shops. You want included a helmet, track pump (floor standing high pressure one), travel pump, spare tubes, patch kit, tyre levers, a multi-tool so you can fix and adjust stuff, an under-seat bag, flashing lights, cages for your drink bottles (bidons), some clear sunnies if you'll ride at night (often best bought at electrical safety stores), cycling knicks (bibknicks are more comfortable because elastic on your waist sucks), ... gee is that everything? Oh, and a year of servicing... and hopefully a mechanic who is happy to show you how to do a basic service so you don't have to keep paying after that.