|okay. if you want something classic that you want to be able to wear for ages, you'd be wise to spend on it(i'd look at least at spending £200, ideally, a good bit more). ie. don't go looking for cheap suits, they date in *seconds*|
shape/colouring-wise, I'd look for pure wool, dark charcoal grey pinstripe or something with an 'invisible' twill, ie something with threads of another colour in, ideally, dark purple,green,blue. Subtle but qualitee. will pick out/work well with yr colouring
shape-wise, if yr going for trousers, have a jacket that finishes just above yr hips, anything longer will make you look like a dwarf.
you have a fab figure, so go for slightly (not massively, you don't want to look like Alexis carrington) fitted jacket, and wide-ish legged but definitely straight-legged trousers. *not* flares. will over-balance.
white fitted shirt.
plain shoes/boots. black.
hope that's helpful.