I'm sequencing using the General Midi and I don't quite understand what MSb and LSB is. Can someone please explain.

I'm trying to sequence some GM files, but when I play thatm back, they are all piano
and one track of drums. Can someone please help me out.

P.S. i'm just learning about midi so please
forgive me for asking any stupid obvious questions.

MSB = More Significant Byte
LSB = Less Significant Byte

The values in all midi messages are 7 bits in length, valid values are 0 to 127.
A Program Change message could select only 128 patches; the MIDI specs include a Bank Select message which is divided in MSB and LSB, making possible to select 16384 banks (128 * 128)and then 128 patches in the selected bank.
The control change for Bank Select is 0 for MSB and 32 for LSB. Each synth model can use both values or only one (0 or 32), depending on manufacturer implementation.
On Roland JV/XP synths, both should be used to select a Bank. Also, Bank Select message are processed only if a Program Change is received after the Bank Select. The GM mode does not receive Bank Select (the GM spec have only 128 patches in one Bank)
Of course, all of this is theory...if you are using a sequencer, then all of this are transmitted automaticaly for you.
If your sequences are played back with piano sound, then the necessary BS/PC messages are not being transmitted to your synth.

Mgomes