Awesome, thanks for that. I'll give RetroPie a try. What emulator did you use for Dreamcast, I want to play some crazy taxi for sure
I believe it's lr-flycast, if not it's Redream. I believe Reicast is the Dreamcast emulator that gets installed by default and that was the one I had problems with. Now, it's been almost 5 years since I first did the install, so maybe they got the bugs worked out, I can't say. I just know the default Dreamcast emulator caused lockups and didn't play nice at the time.
If you're looking for a guide, this one is similar to what I went with when I first did mine:
Turn your Raspberry Pi 4 (or 3 or Zero) into a retro gaming rig with RetroPie.
www.tomshardware.com
For transferring games I liked using the SMB method, which basically involves putting your SD card into a reader, plugging it into your PC and moving the files that way. I've never tried plugging a FAT32 formatted USB into the Pi board itself for transferring ROMs, but that looks like an option too. They don't mention it, but there's a few more things you may want like a Pi case and maybe a few connectors, like a micro-USB to HDMI converter cable so you can hook it up to your TV or PC (The cable is like $2). Cases when I was looking were about $20-$30, I liked the ones that had build in reset/power buttons, some cases have no buttons and you shut them off by pulling the power cable. Make sure it has decent cooling or a good heatsink.
The case I went with back in the day is the Argon ONE Aluminum case for Raspberry Pi 4. There may be better ones now, but it's been gold