If you are coming from the west, then Croydon is a pig to get to – coming from the M4, you’re looking at over an hour (if there is no traffic) to get around the M25 and in on the A23. In rush hour, it’ll be more like 2 hours.
I used to commute from Croydon to Leatherhead, It was 40 minutes minimum, and up to 3 hours.
If you are doing just the one night, stay in Reading and get the fast train in to Paddington. The time you lose on the train will be far less than you’d have taken getting to Croydon.
If you want to come closer in, look at somewhere further west or south-west in town – Twickenham, Chiswick, etc… nicer, less stabby, and much quicker for the drive in.
Dave (ex Croydon resident)