Yes. You can search for pywallet, install it and use that to import the private keys into your main wallet, instead of sending the BTC via a transaction.
It does not work with windows, or does it?

The exact time depends on the value of each address and time.
The formula the client uses is:
priority = sum(input_value_in_base_units * input_age)/size_in_bytes
If priority is >57,600 there is no transaction fee.
Basically it works out to 1 day for 1 BTC. Larger addresses (not total wallet value) require less time, smaller addresses require more time.
Ahm, how do i calculate this?
My client shows the number of confirmations, the date, the 0.05BTC a description. What now?
