As for cables, guess you'll need 4-6ft per interconnect. If you plan to go HDMI from DVD and cable box to reciever..then to tv, that's 3 HDMI to start. $70 per is a fair guess for them. If you have the full deal, add $150-200 for stereo interconnect for vcr, cd (though oppo could do that for you), and digital coax or optical in case you want to skip the HDMI for audio (I would on the DVD player for sure).
As for the power thing, stage two is actually ok. My parents have this one.
http://www.monstercable.com/power/productPagePower.asp?pin=1219&LastPage=PowerBars
If you want to go a tad nicer the stage 3 could be worthwhile.