The flange to focal plane length on the old Minolta MD glass is more than it is on an EOS camera. Therefore, you will lose infinity focus on the lenses.
There are adaptors that have an element in them to correct the image, but they often degrade the image more than anything else.
You are left with 2 options.
1. Convert your camera's mount to Minolta (Easy, reversible, but isn't an option for use in the field if you want to throw a Canon on there.
2. Convert the lenses to an EOS mount via an M42-EOS adaptor, and some work on the lens itself. http://vimeo.com/14891384
The conversion has been done a lot and you will routinely see the lenses up for sale on ebay.
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