A 4" rich field reflector is a good telescope for a beginner. Although it's limited to low powers, its wide angle view and light gathering abilities make it excellent for studying comets, star clusters and nebulae. Be sure to investigate models with a clock drive, which facilitates observations by tracking objects as the earth rotates. It's important to get some hands-on experience with a beginner's telescope before investing in more expensive models.
Beginner's telescopes usually come with three or four eyepieces: 40x to 300x. An instrument of this size has an upward limit of about 100x. You start losing image definition if you exceed. The telescope companies have to make their profit and are not always above selling you eyepieces that you don't really need. It's a good idea to buy an extra eyepiece of about 20x or 30x for wide angle viewing. You don't have to exceed that power when studying comets and most star clusters.
Unfortunately, I can't recommend any particular brand of telescope. It's been nearly three decades since I owned my own observatory.
You should also check Amazon for beginner's books on backyard astronomy. Pat's suggestion that you start off with a good pair of binoculars is sound and practical. This is exactly how I started out when I was still in grade school. A reclining lawn chair and a blanket come in handy when observing the night sky with binoculars.
Good question! I'd like to know the answer also as my daughter is wanting a telescope.~ Mindy
I tried one a few years ago in Texas and could not get used to it. All it did was make my head spin, so I gave it to my then girlfriend's son.