What speaker wire should I get? (Onkyo 570 HTiB)

Just finally got my first HT setup, the Onkyo 570 HTiB. Cheap, yes, but I plan on continually upgrading, just wanted something I could use now.


What speaker wire should I use? The rears will need like 25-30' each.


What gauge would you recommend? From where?


I know Radio Shack has some cheap wire, like $8 for 50' of 16 ga. Would this be good enough for me? I also remember a lot of talk about Home Depot having good cheap wire?


FYI, one of the fronts and the 2 rears will both be run down through the floor into the unfinished basement, then back up. Not sure if I'd need different wire for this.


Also, is there any need to upgrade the subwoofer cable?


Thanks a lot for any help.