Thank for the information so far I'm going to look into this some more. I use RF with an old PAL CRT TV and it looks great although I have to put the brightness and contrast up high to make it look correct lol!
So to summarise, if I buy some NTSC games, they will run in 60hz with no problem, however if I run it through RF, the colours will be wrong, but if I had it modded for composite AV the colours would be right?
I'm very sorry for all the questions, very new to this but I love the 2600 and only owned one for a day! The Super Mario and Sonic Homebrews are games which truly blew my mind!
I think maybe a harmony cart would be the way forward, I hope it's easy to use!