Trying to rebuild an old PC with linux

     So I was at my grandma's house on Saturday clean and get everything ready to move to her new house when we came across her old PC. It is an older PC but not ancient by any means. It exceeds the minimum requirements for xp but i think i am going to try out Linux. It is not that i have given up on Windows as an operating system i am just curious to see what the other one has to offer. So wish me luck and offer me advice as i try to go into a world with out my trusty start button. (or is there a start bar add in for Linux??? I should ask Jake)