Their is no single language which helps you to perform in all the fields and help you in building the software but i can tell you if you have an idea about this languages like Java,
SQL. you can bulid softwares
Getting Back link for your site you can do like this search for the sites in google which has high pr and try to search for dofollow sites even where you are benefited bit more than nofollow sites,an try to do bookmarking ,directories,classifieds ,web2.0 sites,image sharing ,video sharing,Pdf submissions many more do all this you will find backlinks for your site..
Hi ,I have an laptop (Acer) bought 2years Back ,which i'm unable to acess blutooth in it . i'm not able to synchronise with my phone even to share the files from lapi to phone visa-versa.Can any one help me how to activate it pl.