There is no doubt that Phil's advice is good, IF you have the physical space available. If you don't have room for LGB R3, then consider Piko R3 - despite the confusing terminology, they are not the same..... Piko's R3 is a little bit larger than LGB's R2, but significantly smaller than LGB R3...... I know, it would be SO much easier if the industry would standardise.....
Avoid R1 if you possibly can - though many people do use it where they are tight for space, and indeed it works OK especially if you have short locos and stock, but sooner or later you will want to buy some bigger rolling stock and you'll come to regret the choice. If you do end up with LGB R2, don't worry about the lack of R2 points in LGB's range - Trainline45 make some that match LGB R2.
Jon.