Based on what you had posted so far, IMHO prime lens is not your cup of tea.
Side note, the 'background blur' is not going to be the same for your 75-300 on a ff SLR vs a 40d with a 18-55mm.
My suggestion is shoot more with your 18-55 first to test it's limitation and think of creative ways to get 'background blur' (how to get good keepers without spending more)
I tried to have the DOF effect on my 18-55 to get the background blur effect. But I failed terribly... But I saw a friend using her 50mm f/1.8, she could easily get background blur, that's why I was considering lenses with f/1.8...
Will you have any pointers or any online readings?
It is? Not impressed that it was very sharp.
Had this in the past but no longer.
The following commendable:
Canon EF 100 F2.8 (old version)
Leica R 90 F2.8
Contax 60mm (1:1) CZ macro
(Leica 100apo macro - no need to say)
Hasselblad CF 180 F4 (CZ)
It is? Not impressed that it was very sharp.
Had this in the past but no longer.
The following commendable:
Canon EF 100 F2.8 (old version)
Leica R 90 F2.8
Contax 60mm (1:1) CZ macro
(Leica 100apo macro - no need to say)
Hasselblad CF 180 F4 (CZ)