Gear (not clothing) question. I just can't get my head around it.

I'm thick I think so can someone help me as I don't understand gear calculators. Long and short I'm doing Fred Whitton (that's another thread) but let's say for example I have one bike with 53/39 and 11-32 ... And another with 50/34 and 11-28. How close are the easiest gears to one another ?? As in the 39 with 32 combo VS the 34 with 28 combo ? Can someone help me with this ?
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39/32 is 1.219:1
34/28 is 1.214:1
The difference between these two is less than half a percent, or put another way, censored all. You won't notice anything.
HOWEVER if they're both 11 speed cassettes (or the same number of gears anyway) then the 11-28 will have closer ratios than the 11-32, meaning your lowest two or three gears will be better matched, and give you more options to find the right gear to spin up a climb. Bigger gaps between ratios just means you sometimes either spin like a hamster or grind too slow.
All other things being equal between the two bikes, you're better off riding the 50/34 and 11-28 combo in a very hilly course.
Fixed TT 2015-2016
http://www.bikecalc.com/gear_ratios
Well it is and it isn't. If the chainsets both take the same BB you can just swap the 50/34 onto the new bike and have 34/32 as your lowest, and knowing the Witton you'll need it.
In my experience you need to spin up the hills, so go with the compact. I used to have a 53/39 with 11-25, and all my mates on compacts would stay seated far longer into the climb, and all would pull away from me as the climb went on. I change the cassette to a 11-27 and eventually 11-29 and started to feel the benefits.
I now have a 52/36 which was on 11-28, but have swapped to 11-32 for the Fred. Every hill seems that little bit easier, the need to get out of the saddle comes later. The South Downs doesn't have anything like Hardknott though!