Which web browser is good to use in windows xp!opera,chrome,ie,mozilla or any other.?

i use chrome and ie 8,i feel chrome is better.can you recommend me any other WB to use in xp.oh!AND also which OS is better to use today,windows xp,vista or 7.OH!AND ALSO can you guys tell me which microsoft office software is good to use,MS-OFFICE 2003,or 2007 or 2010.