vista and xp

ok so i had xp on my comp but then installed vista. and now when i turn on the comp it gives me 3 options to run
earlier version of windows
windows vista
recovery
when i try to go to earlier version it does a system recovery loading screen and then asks me what i want to run
C:\windows
D:\MiniNT
D:\I386
i choose windows and it then asks me for the admin password,but Geek Squad set up the comp and i dont know what the admin password is(ive been told that the default password is nothing and to just hit enter). so i just hit enter and then it gives me this
C:\windows/ (or something along those lines)
and a list of commands
Attrib
Batch
CD
CHDIR
CHKDSK
CLS
COPY
DEL
DELTE
DIR
DISABLE
DISKPART
ENABLE
EXIT
EXPAND
FIXBOOT
FIXMBR
FORMAT
HELP
LISTSVC
LOGON
MAP
MD
MKDIR
MORE
NET
RD
REN
RENAME
RMDIR
SYSTEMROOT
TYPE
i choose LOGON but it goes back to pick one to run
C:\windows
D:\MiniNT
D:\I386
so my question is how do i get xp to work?