Aright man,  I think i rode past you the other day in winersh, there are loads of riders around that area,  The key man is to keeep practicing, upgrade your 20" get a few parts that will make u inprove, better brakes for a start if you riding V-brakes ( although many members on here would say you cant go wrong with a good set up V hahaah), get a pair of maguras, if u feel you want a 26 then its compleatly up to u, but people may say its easyer to start on 20".  Next time u see some riders in winersh, say hi man!.  keep riding  my names dan send us a messege if u want any more details  .