From the errors, I don't see that DNN is at fault.  They look more like hardware/IIS/ASP.NET/AppPool types of errors.  But, and this is a big but, there's no details shown so there's no way to trace this from what you supply.  IIS logs, event log entries and performance counters would all be important to look at.  Also, without knowing the host or setup, it may simply be you're on an overloaded server.

As for the rest of the questions, you can always save everything and repopulate, provided you have a good database backup.  And maybe some SQL skills.

Jeff

I've only seen this happen twice and both times the people using it were using the blog module pretty hard.  The first time I saw it, I figured the guy had just somehow corrupted a user or something so we just made him rebuild  Here's a copy of the error.  Has anyone ever seen this before:

AssemblyVersion: 04.09.01
PortalID: 0
PortalName:
UserID: -1
UserName:
ActiveTabID: 36
ActiveTabName: Home
RawURL: /Default.aspx?tabid=36&error=RoleName&content=0
AbsoluteURL: /Default.aspx
AbsoluteURLReferrer:
UserAgent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0; Trident/4.0; SLCC1; .NET CLR 2.0.50727; InfoPath.2; .NET CLR 3.5.21022; .NET CLR 3.5.30729; .NET CLR 3.0.30618; OfficeLiveConnector.1.3; OfficeLivePatch.1.3; MS-RTC LM 8; MSOffice 12)
DefaultDataProvider: DotNetNuke.Data.SqlDataProvider, DotNetNuke.SqlDataProvider
ExceptionGUID: 29b7c7a5-6e66-4414-bc70-9e0d12f01d3e
InnerException: RoleName
FileName:
FileLineNumber: 0
FileColumnNumber: 0
Method: System.Data.ProviderBase.FieldNameLookup.GetOrdinal
StackTrace:
Message: DotNetNuke.Services.Exceptions.PageLoadException: RoleName ---> System.IndexOutOfRangeException: RoleName at System.Data.ProviderBase.FieldNameLookup.GetOrdinal(String fieldName) at System.Data.SqlClient.SqlDataReader.GetOrdinal(String name) at System.Data.SqlClient.SqlDataReader.get_Item(String name) at DotNetNuke.Security.Membership.DNNRoleProvider.GetRoleNames(Int32 portalId, Int32 userId) at DotNetNuke.Entities.Users.UserInfo.get_Roles() at DotNetNuke.Entities.Users.UserInfo.IsInRole(String role) at DotNetNuke.Security.PortalSecurity.IsInRole(String role) at DotNetNuke.Common.Globals.IsLayoutMode() at DotNetNuke.UI.Skins.Skin.Page_Init(Object sender, EventArgs e) at System.Web.UI.Control.OnInit(EventArgs e) at System.Web.UI.UserControl.OnInit(EventArgs e) at System.Web.UI.Control.InitRecursive(Control namingContainer) at System.Web.UI.Control.AddedControl(Control control, Int32 index) at System.Web.UI.ControlCollection.Add(Control child) at DotNetNuke.Framework.DefaultPage.Page_Init(Object sender, EventArgs e) at System.Web.UI.Control.OnInit(EventArgs e) at System.Web.UI.Page.OnInit(EventArgs e) at DotNetNuke.Framework.PageBase.OnInit(EventArgs e) at System.Web.UI.Control.InitRecursive(Control namingContainer) at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) --- End of inner exception stack trace ---
Source:
Server Name:

and another:

AssemblyVersion: 04.09.01
PortalID: -1
PortalName:
UserID: -1
UserName:
ActiveTabID: -1
ActiveTabName:
RawURL: /Default.aspx?tabid=36&error=RoleName&content=0
AbsoluteURL: /Default.aspx
AbsoluteURLReferrer:
UserAgent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0; Trident/4.0; SLCC1; .NET CLR 2.0.50727; InfoPath.2; .NET CLR 3.5.21022; .NET CLR 3.5.30729; .NET CLR 3.0.30618; OfficeLiveConnector.1.3; OfficeLivePatch.1.3; MS-RTC LM 8; MSOffice 12)
DefaultDataProvider: DotNetNuke.Data.SqlDataProvider, DotNetNuke.SqlDataProvider
ExceptionGUID: d2ddf386-6b13-48ef-8ada-b9e817945495
InnerException: TabID
FileName:
FileLineNumber: 0
FileColumnNumber: 0
Method: System.Data.ProviderBase.FieldNameLookup.GetOrdinal
StackTrace:
Message: System.IndexOutOfRangeException: TabID at System.Data.ProviderBase.FieldNameLookup.GetOrdinal(String fieldName) at System.Data.SqlClient.SqlDataReader.GetOrdinal(String name) at System.Data.SqlClient.SqlDataReader.get_Item(String name) at DotNetNuke.Entities.Tabs.TabController.FillTabInfo(IDataReader dr, Boolean CheckForOpenDataReader, Boolean CheckForLegacyFields) at DotNetNuke.Entities.Tabs.TabController.FillTabInfoCollection(IDataReader dr, Boolean CheckForLegacyFields)
Source:
Server Name:

Any ideas?