ok this is what helped me to install additional
drivers.
1. download the 32 bit drivers, extract them to a folder if you can. i could not do this and kept getting an error saying windows couldn't run a 32 bit progy etc. if you can extract drivers to a folder skip this next paragraph.
if not you need to try and open them, get the error message, and then wait.
don't close anything. press Win+R to open run window and type "C:\Users\
your user name\AppData\Local\Temp\" find most recent folder that doesn't start with "{" or what have you. mine was "WZSE1.TMP" you should see files and folders that have your printer name and hopefully one that says "drivers."
2. find the .inf file (mine was MP210PR.inf) for your printer and open in notepad. Windows 7 seems to rename printers for its own liking. i have a Canon PIXMA MP210 and Win 7 thinks it's a Canon Inkjet MP210 series Printer. this is the problem. in notepad find wherever your printer name is in parenthesis and correct the name. this took me a few tries to get right. i had to go into Device Manager and copy the name from there. for example
my .inf file read this
Windows2000
[Canon]
"
Canon MP210 series Printer" = CNM_0316XP,
i had to change it to this
Windows2000
[Canon]
"
Canon Inkjet MP210 series" = CNM_0316XP,
you might have to play around with the wording (like including or excluding the word "Printer") to get it right. i had to correct the name in two places in the .inf file, one under Windows2000 and another under Windows XP. (i only changed my MP210PR.inf and not my MP210SC.inf because frankly i couldn't find my printer name anywhere in that gibberish)
3. save file. copy location in address bar, and paste into the "Additional Drivers" browser. ex "C:\Users\
your user name\AppData\Local\Temp\WZSE2.TMP\mp210swin101ea24\
Driver"
this let Windows 7 recognized the drivers for me.
4. by this point i still hadn't closed the original error message about running a 32bit program, so i hope you haven't. i don't know if it makes a difference or not; i wasn't willing to test it. that being said, jump over to your XP machine, find your printer on the network and it should give you the option to install drivers. i don't know how XP will do this because i was doing this with a Vista laptop and all i had to do was double click my printer.
anyways that helped me to actually share between the two OS's. now if you can actually get the printer to print something let me know. for some reason Windows 7 thinks my printer is "Ready" when it's off. i haven't actually been able to print anything from either computer. the printer queue just says "Spooling" and "Printing" but nothing happens. i turned the printer off and Win 7 still thinks it's online. so good luck with that. man i hope this helped.