Oscommerce has two branches, the spiritually inclined Zen-Cart and commercially inclined Cre-Loaded.
Both use same codebase as osc and have a rich set of features. Cre has more intitutive and better looking admin as compared to zen cart and understandably so as CRE has a company behind it.
Altough both have pretty similar basic features there is a subtle difference in the way they treat categories/products.
In Zen-Cart I can disable the whole category and all subcategories/products inside it will get disabled, but it is not possible in cre-loaded. Cre does not support disabling the whole category as such though one can disable individual products.
But there is a flip side to it, in Zen-Cart, one cannot have both product and subcategory within a category, cre on other hand does not have such issue.
For my case I will go with Zen-Cart as disabling the whole category is quite an essential feature.