[losing touch.]

first one: personally no, i wouldn't tell her. you could try flirting with her and see how she reacts. but i wouldn't outright say 'i like you' cos if she's straight [and definitely straight] then she may be a little weirded out and it might compromise your friendship. as for the second scenario, no i don't think she's too old for you. if you like her, and she's into girls then i don't see why you shouldn't tell her you like her or at least flirt with her and get to know her more. see how it goes!