you have problems:
when u see someone swooping to you, block. then teleport up and give a headnut. if u didnt hit him because he blocked, then teleport fast behind him, he doesnt know u r behind him so kick his arse. then he is on the ground. now u can power up ki. if he is stunned make a ki attack. then when he comes u can teleport away if u dont have enough ki. teleport, power up, teleport power up. then u have enough ki to kick his arse or to block.
it is so easy. when 2 ppl attack u because they are lame - that is lame. u cant do anything. you could try to hide or hit one guy so he is away. and then hide. the other guy who formed up in lame team thinks that the other guy is beaten so he attacks him. then attack them with that best ki attack u have.
if u are cell, freezer or krillin, u can use disc. thats really good to get rid of annoying meleeists. with piccolo the sbc is good to, u can teleport after shooting so the guy doesnt know where u r. trunks burning attack blinds them, so be sure u have enough time till the guy comes to fire the attack.