Fool, you're talking about tapering them. Which means they will make them slimmer.
Hemming means your jeans will become SHORTER!!!!
If you want to taper them, just take your jeans to suit place that does alterations or go to Nordstroms or something and ask if they can taper from the inside of the pant leg.
Ask what their policies are if they ruin your jeans are. Not sure if places have anything like that but I'd ask since they're not some $50 jeans