Re: What's in fashion for us 'older' ladies?
I like that stiff jamavar banarsi and kattan silk/raw silk material for middleaged ladies. Also, I wouldn't be afraid to try out chiffon! It's not as sheer as you think, and has a great "slimming" effect as opposed to the heavier brocade I mentioned above. Also, I like silk organza for formal wear on older ladies. I think this results in a dignified and polished look.
As for style...I'd do a narrow pant cut (not bootcut pants)...with a slight slit at the botom if you're feeling a little edgy with a shirt that is knee length. Anything shorter and you'll look like you're trying way too hard!
Remember, you're aim is clean lines and nothing overtly fussy!