This topic has been discussed more times than you can shake a stick at,
yet it's amazing how often people basically get it wrong.
GE offers a range of products targeted at consumer home improvement. Basically, there are two product lines: Silicone I and Silicone II. The only significant difference is that Silicone I is acid cure (it gives off acetic acid as it cures) while Silicone II is ammonia cure (it gives off ammonia as it cures). It's arguable that the cure has no impact on suitability for aquarium use, though typically acid cure silicone is stronger, with the downside that it's slower to cure.
Both Silicone I and Silicone II are available as "window and door" or "kitchen and bath." The difference between these variants is that the kitchen and bath product has a mold inhibitor. It's taken for granted on aquarium forums that the mold inhibitor is harmful, though honestly I don't recall ever seeing anything that proves that.
All of that information would point to Silicone I window and door as the best of these products.
When all is said and done, it's important to note that NONE of these products are "strong" when compared to other varieties of silicone. If you're doing a project where absolute strength is not a requirement it's probably OK and as noted above, GE Silicone I is very commonly used around fish tanks. If you're doing something that requires good strength, you're probably better off looking elsewhere. Momentive RTV108 or GE SCS1200 are common choices for a "better" silicone though they won't be in a generic hardware store. You can get them at places like Grainger, or online at Amazon or mcmaster-carr.