I switched a while ago from Mac OS X (Leopard) to Ubuntu (Gutsy) and didn't encounter any serious problems until about a month ago when Ubuntu crashed for seemingly no reason. I tried to boot my computer and for a while nothing happened, then an image came up of a folder with a question mark on it.

So, I've been using the ubuntu liveCD for about a month tinkering around and trying to install...but the installer gets to about 48% and then freezes.

Throughout this process, I lost all of the files in my /home folder and seemingly all of my hard drive partitions. This is interesting, because at first I still had my files and the installer detected my existing partitions, but now it doesn't do it at all.

Here are some notable command line outputs:

ls /dev:
1-2 ptyc0 ptyqf ptyve ram7 tty7 ttyec ttyt7 ttyy6
3-2 ptyc1 ptyr0 ptyvf ram8 tty8 ttyed ttyt8 ttyy7
4-1 ptyc2 ptyr1 ptyw0 ram9 tty9 ttyee ttyt9 ttyy8
5-4 ptyc3 ptyr2 ptyw1 random ttya0 ttyef ttyta ttyy9
adsp ptyc4 ptyr3 ptyw2 rtc ttya1 ttyp0 ttytb ttyya
agpgart ptyc5 ptyr4 ptyw3 scd0 ttya2 ttyp1 ttytc ttyyb
audio ptyc6 ptyr5 ptyw4 sequencer ttya3 ttyp2 ttytd ttyyc
bus ptyc7 ptyr6 ptyw5 sequencer2 ttya4 ttyp3 ttyte ttyyd
cdrom ptyc8 ptyr7 ptyw6 sg0 ttya5 ttyp4 ttytf ttyye
cdrw ptyc9 ptyr8 ptyw7 shm ttya6 ttyp5 ttyu0 ttyyf
console ptyca ptyr9 ptyw8 snapshot ttya7 ttyp6 ttyu1 ttyz0
core ptycb ptyra ptyw9 snd ttya8 ttyp7 ttyu2 ttyz1
disk ptycc ptyrb ptywa sndstat ttya9 ttyp8 ttyu3 ttyz2
dri ptycd ptyrc ptywb sr0 ttyaa ttyp9 ttyu4 ttyz3
dsp ptyce ptyrd ptywc stderr ttyab ttypa ttyu5 ttyz4
dvd ptycf ptyre ptywd stdin ttyac ttypb ttyu6 ttyz5
dvdrw ptyd0 ptyrf ptywe stdout ttyad ttypc ttyu7 ttyz6
fd ptyd1 ptys0 ptywf tty ttyae ttypd ttyu8 ttyz7
full ptyd2 ptys1 ptyx0 tty0 ttyaf ttype ttyu9 ttyz8
fuse ptyd3 ptys2 ptyx1 tty1 ttyb0 ttypf ttyua ttyz9
hpet ptyd4 ptys3 ptyx2 tty10 ttyb1 ttyq0 ttyub ttyza
initctl ptyd5 ptys4 ptyx3 tty11 ttyb2 ttyq1 ttyuc ttyzb
input ptyd6 ptys5 ptyx4 tty12 ttyb3 ttyq2 ttyud ttyzc
kmem ptyd7 ptys6 ptyx5 tty13 ttyb4 ttyq3 ttyue ttyzd
kmsg ptyd8 ptys7 ptyx6 tty14 ttyb5 ttyq4 ttyuf ttyze
log ptyd9 ptys8 ptyx7 tty15 ttyb6 ttyq5 ttyv0 ttyzf
loop0 ptyda ptys9 ptyx8 tty16 ttyb7 ttyq6 ttyv1 urandom
loop1 ptydb ptysa ptyx9 tty17 ttyb8 ttyq7 ttyv2 usb1
loop2 ptydc ptysb ptyxa tty18 ttyb9 ttyq8 ttyv3 usb2
loop3 ptydd ptysc ptyxb tty19 ttyba ttyq9 ttyv4 usb3
loop4 ptyde ptysd ptyxc tty2 ttybb ttyqa ttyv5 usb4
loop5 ptydf ptyse ptyxd tty20 ttybc ttyqb ttyv6 usb5
loop6 ptye0 ptysf ptyxe tty21 ttybd ttyqc ttyv7 usbdev1.1_ep00
loop7 ptye1 ptyt0 ptyxf tty22 ttybe ttyqd ttyv8 usbdev1.1_ep81
MAKEDEV ptye2 ptyt1 ptyy0 tty23 ttybf ttyqe ttyv9 usbdev1.4_ep00
mem ptye3 ptyt2 ptyy1 tty24 ttyc0 ttyqf ttyva usbdev1.4_ep81
mixer ptye4 ptyt3 ptyy2 tty25 ttyc1 ttyr0 ttyvb usbdev1.4_ep83
net ptye5 ptyt4 ptyy3 tty26 ttyc2 ttyr1 ttyvc usbdev1.4_ep84
null ptye6 ptyt5 ptyy4 tty27 ttyc3 ttyr2 ttyvd usbdev2.1_ep00
nvidia0 ptye7 ptyt6 ptyy5 tty28 ttyc4 ttyr3 ttyve usbdev2.1_ep81
nvidiactl ptye8 ptyt7 ptyy6 tty29 ttyc5 ttyr4 ttyvf usbdev3.1_ep00
oldmem ptye9 ptyt8 ptyy7 tty3 ttyc6 ttyr5 ttyw0 usbdev3.1_ep81
port ptyea ptyt9 ptyy8 tty30 ttyc7 ttyr6 ttyw1 usbdev3.2_ep00
ppp ptyeb ptyta ptyy9 tty31 ttyc8 ttyr7 ttyw2 usbdev3.2_ep83
psaux ptyec ptytb ptyya tty32 ttyc9 ttyr8 ttyw3 usbdev4.1_ep00
ptmx ptyed ptytc ptyyb tty33 ttyca ttyr9 ttyw4 usbdev4.1_ep81
pts ptyee ptytd ptyyc tty34 ttycb ttyra ttyw5 usbdev4.3_ep00
ptya0 ptyef ptyte ptyyd tty35 ttycc ttyrb ttyw6 usbdev4.3_ep02
ptya1 ptyp0 ptytf ptyye tty36 ttycd ttyrc ttyw7 usbdev4.3_ep03
ptya2 ptyp1 ptyu0 ptyyf tty37 ttyce ttyrd ttyw8 usbdev4.3_ep81
ptya3 ptyp2 ptyu1 ptyz0 tty38 ttycf ttyre ttyw9 usbdev4.3_ep82
ptya4 ptyp3 ptyu2 ptyz1 tty39 ttyd0 ttyrf ttywa usbdev4.3_ep83
ptya5 ptyp4 ptyu3 ptyz2 tty4 ttyd1 ttys0 ttywb usbdev5.1_ep00
ptya6 ptyp5 ptyu4 ptyz3 tty40 ttyd2 ttyS0 ttywc usbdev5.1_ep81
ptya7 ptyp6 ptyu5 ptyz4 tty41 ttyd3 ttys1 ttywd usbdev5.3_ep00
ptya8 ptyp7 ptyu6 ptyz5 tty42 ttyd4 ttyS1 ttywe vcs
ptya9 ptyp8 ptyu7 ptyz6 tty43 ttyd5 ttys2 ttywf vcs1
ptyaa ptyp9 ptyu8 ptyz7 tty44 ttyd6 ttyS2 ttyx0 vcs2
ptyab ptypa ptyu9 ptyz8 tty45 ttyd7 ttys3 ttyx1 vcs3
ptyac ptypb ptyua ptyz9 tty46 ttyd8 ttyS3 ttyx2 vcs4
ptyad ptypc ptyub ptyza tty47 ttyd9 ttys4 ttyx3 vcs5
ptyae ptypd ptyuc ptyzb tty48 ttyda ttys5 ttyx4 vcs6
ptyaf ptype ptyud ptyzc tty49 ttydb ttys6 ttyx5 vcs7
ptyb0 ptypf ptyue ptyzd tty5 ttydc ttys7 ttyx6 vcs8
ptyb1 ptyq0 ptyuf ptyze tty50 ttydd ttys8 ttyx7 vcsa
ptyb2 ptyq1 ptyv0 ptyzf tty51 ttyde ttys9 ttyx8 vcsa1
ptyb3 ptyq2 ptyv1 ram0 tty52 ttydf ttysa ttyx9 vcsa2
ptyb4 ptyq3 ptyv2 ram1 tty53 ttye0 ttysb ttyxa vcsa3
ptyb5 ptyq4 ptyv3 ram10 tty54 ttye1 ttysc ttyxb vcsa4
ptyb6 ptyq5 ptyv4 ram11 tty55 ttye2 ttysd ttyxc vcsa5
ptyb7 ptyq6 ptyv5 ram12 tty56 ttye3 ttyse ttyxd vcsa6
ptyb8 ptyq7 ptyv6 ram13 tty57 ttye4 ttysf ttyxe vcsa7
ptyb9 ptyq8 ptyv7 ram14 tty58 ttye5 ttyt0 ttyxf vcsa8
ptyba ptyq9 ptyv8 ram15 tty59 ttye6 ttyt1 ttyy0 watchdog
ptybb ptyqa ptyv9 ram2 tty6 ttye7 ttyt2 ttyy1 xconsole
ptybc ptyqb ptyva ram3 tty60 ttye8 ttyt3 ttyy2 zero
ptybd ptyqc ptyvb ram4 tty61 ttye9 ttyt4 ttyy3
ptybe ptyqd ptyvc ram5 tty62 ttyea ttyt5 ttyy4
ptybf ptyqe ptyvd ram6 tty63 ttyeb ttyt6 ttyy5
[note no sda]

ubuntu@ubuntu:~$ ls /dev | grep sda
[no output]

ubuntu@ubuntu:~$ sudo fdisk /dev/sda

Unable to open /dev/sda
ubuntu@ubuntu:~$ sudo mount -t ext3 /dev/sda /mnt/temp
mount: special device /dev/sda does not exist
ubuntu@ubuntu:~$ sudo fdisk -l
ubuntu@ubuntu:~$
[no output]

Everyone I have talked to about this has been thoroughly baffled. Any help would be immensely appreciated.