Newbie with Cakewalk and MIDI questions

[Big Yellow]

Hi. I'm relatively new to home recording and very new to MIDI, and I'm
hoping someone here can answer a few questions for me. I have a Gateway
2000 solo laptop running Windows 95. I'm using Cakewalk Guitar Studio.
My computer also tells me that I have Yamaha OPL3-SAx Sound System,
Yamaha SXG50 driver, and Yamaha SoftSyth S-YXG50, although I don't
really know what any of that means, which is part of my problem. My main
instrument is guitar, and I play mostly roots-rock, alt-country type
stuff. I record with a Roland VS-840EX. What I'm hoping to do is use
Cakewalk to sequence (I believe that is the correct term) MIDI bass
lines, drums, keyboard parts, etc. and synch them with vocals, acoustic
& electric guitar, and mandolin that I record on the VS-840EX. I don't
have a MIDI keyboard or controller, so I've been entering notating the
stuff I want Cakewalk to play in the note staff, which is working ok for
me for now, although I hope to get a midi controller soon. Here are my
questions:

1)I'm having a problem accessing the XG drum kits and banks in Cakewalk.
If I select an XG drum kit or bank, I get General MIDI sounds. Any idea
why this might be?

2)Right now I don't have a MIDI interface, so I've been sequencing bass
tracks in Cakewalk, running that through a line out into the VS840EX,
recording it, and then overdubbing guitar and vocals. What I'd like to
do is be able to synch Cakewalk and the VS840EX, so I can go back and
add stuff later. The laptop doesn't have a MIDI port or a joystick port,
but it does have a USB port. What type of MIDI interface should I
consider? Midisport 1X1? 2X2? Portman? Any advice would be very much
appreciated.

3)Any suggestions on a relatively inexpensive MIDI controller?

Thanks in advance