Wide girthed beginner snakes, 4-5 ft. Tricky one...
Well, I've never really heard of Ball Pythons being moody. Those I've encountered have been very meek and mild. Slow moving with cute faces... Don't move much, but what the heck. The only catch which could drive a beginner nuts, is they can occasionally be very picky feeders and/or fast for months at a time. Wild caught bps are far more likely to have feeding issues than captive bred ones. If you go with a well started captive bred one willingly eating f/t food, you'd probably be okay.
And that's the only wide girthed beginner snake 4-5 feet that I can think of.
The only other wide girthed snakes good for starting are far smaller, the western hognose 2-3 ft(which is very cute, docile, but as a warning carries very mild rear fanged venom, and you'll have to be sure the individual eats unscented f/t mice) and the Kenyan Sand boa which is thick bodied but gets to only around 2 ft.
Then there's Florida Kings which are thick bodied but get over 5 ft (I think) pine and bull snakes which have more heft than a corn snake but also may (depending on the species) grow to over 5 ft. You can check their respective forums for details..
Of the snakes that fall into your length range (approximately) if not your width range, are the corn snake (of course) the California King snake (even skinnier) and spotted and childrens pythons (which I'm frankly only guessing on, don't know much about them)
All things considered, a very well started ball python recieved from a reputable breeder may be your best bet.
Good luck.
-----
0.2 chickens (Falcon & Condor)
0.2 dog mutts (half ownership, only mine when they misbehave, Lucy & Amy)
0.1 Halflinger horse (Crissy)
0.0 Arizona Mountain Kingsnake (coming soon)
1.1 parents
Still searching for 1.0 WC human