Hi Lorrainna, Custom forms can't be attached to Hours, and so you wouldn't be able to do a calculated field to populate based on whether it is one of the two hours types your interested in. Luckily I don't think that would be a problem....I would suggest you just create an Hours report which is filtered down to the two hour types you're interested in. You can then configure matrix groupings to group at whatever levels you're interested in and Sum the planned hours values. Let me know if this isn't what you were after or you need some more info.
Regards, David Cornwell