I have been dual booting vista home basic and gutsy since about february, and I just started getting this issues yesterday. I have a dell inspiron 1521 with 2gb ram. No problems, even with wireless up until now.
If I log into 1 operating system, the next time I log into other it will lock up the first time, and after a hard reboot I can get in. I am not sure if this is an ubuntu problem or a vista problem, but I don't allow either of them to update, so it is most likely not that. I did shrink my vista partition a week ago in anticipation of triple booting, but this problem didn't not occur or I didn't notice it until now.
Now, I planned on wiping 7.1 in order to install 8.04, but I read earlier this morning about a kernel update that kills wireless. If this is the case, I am stuck with gutsy.
Thanks in advance, I hope my issue isn't too obscure.