I have old 45’s which have scratched grooves due to the wrong needle being used. Is there anything I can do with Audacity to minimize this sound? I have an ION USB turntable.
You’re playing a damaged 45 on the worst turntable ever made.
Do you know anybody who still has a top quality turntable with a good stylus?
In a word, no.
Not much - you can try the Equalizer effect (use Audacity 1.3 rather than 1.2 - the Equalizer is much improved in 1.3, as is just about everything else).
Nothing you can do in Audacity, but this might help: