msn 4.7 and 6.0

this may sound stupid if it does please forgive me ok. When i bought my computer which uses win. xp it came loaded with msn 4.7. i went in and downloaded 6.0 when it came out. I went into my firewall and blocked 4.7 from accessing the internet because i wanted to use 6.0 instead. all was working fine till yesterday when my friend was having a problewm on her puter. we decided to try the remote assistance. I know it messed up because 4.7 came up trying to access the internet and i clicked on yes, this time only when the firewall came up. since then whenever i get on the internet it seems as if 4.7 trys to come on. messenger says i cant log in because i have logged into msn from another location. yet at the same time 6.0 is logged in fine. my question is this, can i make 6.0 my default and can i take 4.7 out without messing anything up? hope the way i worded this was not too confusing. Thanks