I've heard radio shack solder is good and 40W should be plenty. I HIGHLY recommend using solder paste or flux as it's known. I don't see how anyone can justify not using it really. It makes the solder stick instantly to anything it touches and melts away so you didn't even know it was there. It also cleans your tip instantly but can be mildly corrosive if used too much so ya gotta be careful. I use a Hakko 936 and burned up the first tip after 2 months but been going on the 2nd one for over 4 now and it works as well now as it did new.