I like skirt suits, but haven't found one that I could afford (read: bring myself to spend money on 😛 ) that fit well that I liked, so I wear pant suits. I think either is fine, just a matter of which you will feel more confident in (which in turn determines which you'll look more confidant in). I usually wear heels with my suit, but it's about the only time I wear them, since my feet always complain for a week afterwards. 😐
Hair, I wouldn't say it has to be all up (all up looks better on some faces than others – mine is face that does better without the hair pulled off sharply), but you want it to look professional and most importantly not require any touching, adjusting, etc. For me, a variation on the classic half-up do has worked best. I leave the first inch or so of my hair down (side-parted) and tucked behind my ears, then do the rest of the top half of my hair pulled back into a barrette. Keeps some softness around my face and keeps my hair out of the way. Some people can leave their hair completely down, brushed smooth, and never touch it. I interviewed someone last week that was like that. It looked professional, neat, etc., and didn't “interrupt” the interview. However, when my hair is down, it looks messy very quickly and falls in my way so I can't ignore it. So, for her it worked; for me it wouldn't. Personally I'd avoid the plain pony tail, since I think it can look more athletic/casual, unless it's done right…and I don't have the skill to do it “right” or even know what makes it “right”, just know some people can pull it off but it's far from everyone.
I usually have carried my purse and have seen purses carried, but would advise towards a professional purse. This isn't the time for Minnie's Backpack, but something solid/mature/professional is fine IMHO. I do have a portfolio I carry too with resume copies in it – next time, I might try just bringing that (with perhaps my Driver's License in it) and my keys instead of the purse. Something to consider at least…
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