First one is a 11g card while the second is 11b. This will limit your speed to the 11b range (or 11megabits a second) and the range will be decreased. You should manage 10M through two walls (I'm currently writing this in my garage while the wireless router is inside the house - probably as far away as that). One thing worth mentioning is arial placement is important as PCI cards tend to have a large metal case in front of the arial when they try and connect
You are probably better off spending the extra few quid and getting
http://www.ebuyer.com/customer/products/index.html?rb=2892322173&action=c2hvd19wcm9kdWN0X292ZXJ2aWV3&product_uid=63002Then you'll be able to swap files 5 times as fast
You password encrypt the link (believe both support WEP128 and/or WPA) and then can set up shared areas on each others discs to copy files to/from.