Miam, the purpose of the eyedrops (some kind of atropine-related substance) is to dilate the pupil so that the optometrist or ophthalmologist can see inside the eye. This is particularly the case with younger children, as it's hard to test them reliably any other way.
If your child has blue eyes, one set of drops is usually enough, if she has brown eyes, it may take two goes. Some hospitals will offer a spray instead of drops, which feels less 'wet', and so may be less upsetting. The drops take about half an hour to take effect, and then another few hours to wear off. During this time your child will have blurred vision and may find the light hurts her eyes.
Personally I found bribery the best way to deal with the situation -- whipping out a packet of smarties at the crucial moment is a great distractor. Since it's her first time, she won't know what's coming down the tracks, which gives you the advantage!
If she can see much better with her glasses, you'll probably have very little resistance to wearing them. We've never had any problems in that department, tho' we've had occasional stupid comments from other children. dd1 never really understood the point of these, since from her perspective, she could see with her glasses on, and couldn't see without them. Something of a no-brainer.
But do post again or CAT me if you want more info.