Some things you might wanna try ... I warn you tho I'm a bit of a n00b myself with Cacti so take it or leave it
Change poller back to cmd.php (less to worry about that way, although I've found cactid is better at not hanging)
Disable all data sources except the ones you know work, or maybe only one on localhost ie. the one most likely to be successful (to make sure a data source isn't the problem)
If you changed the poller to cmd.php - also set the maximum concurrent poller processes (same page you pick cmd.php or cactid) to 2. When you retry polling, if you get "Waiting on 2/2 pollers" something is fundamentally broken with the poller. If you get "Waiting on 1/2 pollers" then it's more likely to be a data source problem. Set it back to 1 when you're done testing, particularly if you intend switching back to cactid.
Check your filesystem permissions with filemon or procmon (
http://www.sysinternals.com ) if you get access denied anywhere on the cacti processes, fix these. (there is an automated script somewhere that sets the permissions but I had to modify it so check the script first)
HTH
[size=75][b]Win2003 x86 SP1 | IIS 6 | Cacti 0.8.6i | Cactid 0.8.6i | MySQL 5.0.24 | PHP 4.4.4 | RRD 1.2.15 | NetSNMP 5.3.1 | Cygwin 1.5.23 | P4 2.1GHz | 512MB | 300GB RAID1[/b][/size]