Two-part headphone question

For the first time in decades, I have an amplifier with a headphone jack. (It's a Creek Audio Destiny Integrated Amplifier.) Two questions:

1) I'd like to give 'phones a try, but I don't want to spend a ton in case I don't end up enjoying the experience. Can folks recommend a decent and relatively inexpensive pair of headphones that a boy might try to check out this whole (forgotten) world of listening with the speakers attached to your head?

2) As the most comfortable seat in the joint is a fair distance from the amp, I'm wondering if one can run a kind of headphone cord extender (quarter-inch female to quarter-inch male) without causeing any problems?

Thanks for any direction you might be able to give me on this one.

Howard