The 3/4 is actually to wide to correctly tension on a 14 inch bandsaw.
The 1/2 inch is about the limit for a 14 inch, and the 1/4 inch is to thin for resawing.
Get the 1/2.

Depending on the work he does, you might want both the 1/4" and 1/2" blades. Generally, narrower blades are better for going around curves while wide blades are good for cutting straight lines. Blades with more teeth are better for cutting thinner stock, and fewer teeth are better for thicker stock. I agree that the 3/4" blade is too much for that saw.

Thanks! I might end up getting both.

If I may, I would suggest you place a phone call to Suffolk Machinery. They manufacture and supply a brand of bandsaw blades called Timberwolf. They are very highly regarded and reasonably priced. They have many different sizes and tooth configurations. The real advantage is that if you call them, you can talk to a real live person who will be able to recommend the best blade, based on several factors. The saw is just one of the factors, others include type of material typically being cut, thickness and type of cut (resaw vs scroll). They have a website as well. Don't know it off hand, but do a search on Suffolk Machinery and it will come right up. Good luck, HTH.

Agreed on Suffolk blades - very nice, and their shipment would include extensive instructions on proper tensioning, which is more important than even most experienced woodworkers realize.