I would sand any particularly heavy callus, then moisturise- which one you use depends on personal preferance.
Creams are light and easy to use (not greasy) but don't give as much moisturising action.
Ointments are greasy (and some people don't like that), but give the best moisturising.
There's 5 levels essentially:
Light- E45 lotion/Aveeno ointment/Dermol 500 lotion/aqueous cream
Creamy- Diprobase/E45 cream/Dermol 500 cream/Aveeno cream
Rich Cream- Unguentum, Doublebase gel
Greasy- Hydromol ointment/ epaderm ointment/emulsifying ointment
Very Greasy- 50:50 liquid soft paraffin and white soft paraffin
Personally, I like DoubleBase Gel (a good compromise between greasy and light) or emulsifying ointment for when I've got really dry skin. I wouldn't bother with other stuff as it's expensive, has other shit in it you don't need and isn't any better.
Plus those on the list are fairly cheap, emulsifying ointment is about 3 quid for 500g.
Hope that helps.