I would go with the semi-auto shotgun, as long as your budget stretches to $1000 or $1200. Get something decent, and you'll have it for life. I find semi-autos are way easier for beginners, compared to pumps. I've watched so many new pump users short stroke it, accidentally open the action with recoil, then close it again without realizing (action then locks) and be unable to pump the next round, etc. Semi-auto is comparatively foolproof, you load it, charge it, and once you start shooting the gun does the rest for you and you can just concentrate on your target.
The best shotgun is something that fits you really well and points naturally at a target. Try LOTS of guns in the store, shoot your buddies' guns, handle everything you can before you make a decision. Don't buy a gun online that you have not handled. That fit is all important. If you're like 6 foot or over, beware some guns like Mossberg pumps with the short length of pull (distance between the trigger back to the end of the stock on your shoulder). I find this is the killer aspect for fit, from experience, where other people shoot these way better than I do!
I'd get something with a synthetic stock, they are super durable and you won't have that hesitancy when it comes to taking your lovely new gun out into foul weather, disgusting swamps, tree-covered (scratchy!) creeks or just transporting it all over the trails in your truck.
Whatever you choose, good luck and safe hunting!