Are there any disadvantages to rails on a windows computer

You will likely encounter more problems and get less help from people on the internet, since most developers work on Macs and Linux machines (so there's more help around). Also, a LOT of commands used in the console won't work in Windows (even if you use and emulator like CMDER or Git Bash), so you won't be able to follow most courses/tutorials unless you figure out Windows terminal counterparts for commands. After working under Windows for a few months I also discovered that stuff works faster under Linux compared to Windows. When working with other people with version control, you need to set up your git properly, because the end of line symbols work differently for files under Windows and Linux/Mac systems.