How to transfer Files Mac to pc

I really need help I seen/read many ways to transfer Mac to pc files I'm talking about mainly large files like hd videos and there are ways I tried but don't work I'm using Mac os x lion and trying to transfer to windows 7 I don't know I am willing to buy or buy a port if it guarantees to transfer files preferably fast with large files I need speed. I have tried quite a few ways an some was I haven't attempted because it seems to much work and feel like there should be something simpler such as changing formats for files FAT32 to something else and I don't have time for that. I have tried network through router and Ethernet even direct connection but can't seem to get it to work right I see the pc in finder but I cannot connect to it when i try to connect It takes forever to connect then It says could not connect. I have also purchased a wire (targus) and then found out it don't work with Mac os lion. I have also tried the migration assistant but it seems that only works the opposite way I want it to transfer to the pc not to the Mac... I am willing to buy a pci drive for my pc in order to be able to do it but I don't know how it would work I mean like a FireWire drive but I believe that's what I need to change format and I don't wanna risk losing anything which I heard is possible doing this. Also I'm dealing with large amount of hd footage which is like around 100GB so yeah I need speed so 16/32/external hardrives is an avoiding option. If there's was some help like a video or instructions for the best way would be very satisfactory and much appreciation.