I have a linksys wireless G with speedbooster, (the older original).
I need an adapter for a desktop PC.
1. Is any brand compatible, (netgear seems to have a good price)?
2. is one adapter type better than another, like
a internally mounted pci card versus an external usb adapter?
I'm just trying to save money but I don't want to have connectivity issues.
They should all be compatible at the basic 802.11b or 802.11g spec (11b for 11Mbps and 11g for 54Mbps). You will need to buy the same brand to take advantage of the "speedbooster" stuff.
Either adapter type is OK.
If you buy a PCI adapter, get one with a removable antenna so you can add an external antenna if needed for signal strength.
Don't buy a USB adapter unless you have USB 2.0 ports. USB 1.1 ports will only operate at 802.11b speeds. Also, if you buy a USB adapter, get one with a long enough cable that you can position the antenna for best reception.