I would recommend NOT freezing buds.
To keep them fresh, I use one of those seal-a-meal things (NOT the kind that sucks out the air) and store them in the basement (cool & dark). They will keep for at least a year that way. I'm smoking some of last years harvest right now and they're as good as the day they were sealed (actually they are a bit smoother now).
If you're only gonna store them for a few weeks, put them in a tupperware container and keep in the fridge.