Does it matter which static IP address I choose for my devices?

Technically it makes no difference what IP address your device has.

Usually consumer/home routers will set the DHCP range to be high numbers, ie. 100 to 200 in which case it makes sense to put static IP's outside that range.

I do tend to put things I use often at "easy numbers".

I am setting a static IP address for my desktop PC and reserving that address on the router so that it only assigns that address to my PC.

It's a wrong (but possible) practice, especially when MAC stored in DHCP reservation and real MAC address of that IP differs (can occur in future, by damaged NIC replacing, for example). Additionally any change at DHCP which is transferred to clients (DNS address or static route change, for example) will not be transferred to Your station, You must check for that changes and apply them on Your station "by hands".

The better solution is to use IP address out of DHCP scope range. But the problem with manual change tracking is retained.

The best solution is in use dynamic addressing with static reservation plus the same settings in alternative configuration applied when DHCP is not available. The problem with manual change tracking is retained too (for alternative config only), but not so significant as in previous case.

Is there any advantage or disadvantage to choosing certain IP addresses?

No, if You use IP addresses from "private" subnets (for IPv4 see RFC1918). Any IPv4 address is some 4-byte long value, not more.

If you understand subnetting, then either would work. If you don't, then keep that 3rd digit the same throughout the building, so everything is 192.168.1. nnn - or more specifically, whatever the router uses for defaults - some use 192.168.0.x for example. There's no reason, at consumer level, to force any change in that.

Your router's DHCP server will have a 'pool' it selects its assignments from. Sometimes this will be the full range from 192.168.1.1 - 192.168.1.254

Unless the router automatically removes any static mapping from the remaining pool, then first ensure you can adjust that pool manually, to avoid potential conflict. One way would be to reduce the pool to 192.168.1.20 upwards, then assign your static devices below that.
As Mikael already said, that leaves the 'easy numbers' for your common devices.
No number is any "better" than any other, so just use memorable ones.