hai
i think u r laptop installed with win98,is not proper working because some files from system 32 is lost thats why u r not able to boot in to os,so frm my openinon u should upgrade u r laptop...

frm u t sentence i understand that u r computer is having 3 partitions ie c,d,e,as u said c is installed with win98,d is free,and e is installed with linux,at that time u were asked to select the os...

ok if u r windows media player is not working check the settings of mediaplayer and if u r media player settings is fine then check the audio settings of u r system,i think u r system sound setting...

i think u forgot u r administerator password to open u r os in u r computer,hope u made an password with its hint,so just after power on u r pc and then when it aks to insert password in...