You haven't said which version of Excel. According to the help in 2007, Lotus 1-2-3 formats are no longer supported.
However, you might be able to export to a different format in Lotus, and import that into Excel, or you could use a format converter such as this one:
http://www.processtext.com/abclotus.html
(I'm not recommending it - there are many to be found if you type "Convert Lotus 123 to Excel" into Google.)
Some earlier versions of Excel could import Lotus files directly.
If your question is about physically getting the files from one machine to another, the easiest and cheapest method is probably to use a USB memory stick.