Even if we exclude their success in the 50's or 60's and we count only the results in Champions League (the competition as it is in the last 19 years), Real are still one of the best.
Say that a CL win brings 10 pts, a lost final 5 pts, lost semi 3pts and lost quarter 1 pt, this is how the top 10 standings would look
01. Milan 49 ( 3 won CLs, 3 lost finals, 1 lost semi, 1 lost quarter)
02. Barcelona 49 (3 won CLs, 1 lost final, 4 lost semis, 2 lost quarters)
03. Manchester United 44 (2 won CLs, 2 lost finals, 3 lost semis, 5 lost quarters)
04. Real Madrid 42 (3 won CLs, 3 lost semis, 3 lost quarters)
05. Bayern 31 (1 won CL, 2 lost finals, 2 lost semis, 5 lost quarters)
06. Juventus 30 (1 won CL, 3 lost finals, 1 lost semi, 2 lost quarters)
07. Liverpool 20 (1 won CL, 1 lost final, 1 lost semi, 2 lost quarters)
08. Ajax 19 (1 won CL, 1 lost final, 1 lost semi, 1 lost quarter)
09. Chelsea 19 (1 lost final, 4 lost semis, 2 lost quarters)
10. Inter 17 (1 won CL, 1 lost semi, 4 lost quarters)